JANUARY & FEBRUARY, 1996

US ISSN 0013-872X NO. 1

ENTOMOLOGICAL NEWS

Fissimentum, a new genus of drought tolerant Chironomini (Diptera: Chironomidae) from the Americas and Australia P.S. Cranston, U. Nolte 1

Life history of the weevil Euhrychiopsis lecontei, a potential biological control agent of Eurasian watermilfoil S.P. Sheldon, L.M. O'Bryan 16

Central American Tortopus (Ephemeroptera: Polymitarcyidae): a unique new species and new country records C.R. Lugo-Ortiz, W.P. McCafferty 23

New species of Nadleria (Psocoptera: Lachesillidae) from the Tambopata Reserved Zone, Madre De Dios, Peru

Alfonso N.G. Aldrete 28

Effectiveness of combining flotation and staining techniques when sorting benthic invertebrates

D.L. Hall, D.L. Wood, D. L. Moorhead, R. W. Sites 33

Records of Propylea 14-punctata (Coleoptera: Coccinellidae) from Long Island, New York: evidence for a naturalized population before 1991

Douglas Yanega 36

Two new species of Diplocentrus (Scorpiones:

Diplocentridae) from Mexico D.A. Fritts, W.D. Sissom 39

First Texas records of five genera of aquatic beetles (Coleoptera: Noteridae, Dytiscidae, Hydrophilidae) with habitat notes

S.K. Jasper, R.C. Vogtsberger 49

The Mayflies (Ephemeroptera) of North America Online

W.P. McCafferty 61

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Vol. 107, No. 1, January & February, 1996

FISSIMENTUM, A NEW GENUS OF DROUGHT-TOLERANT CHIRONOMINI

(DIPTERA: CHIRONOMIDAE) FROM THE AMERICAS AND AUSTRALIA1

Peter S. Cranston2, Ulrike Nolle3

ABSTRACT: The genus Fissimentum is described from all life history stages for a previously re- cognized but unreared larval taxon "Tendipedini genus A" of Roback, 1966. A Neotropical species Fissimentum desiccatum, here described for Roback's (1966) species 4, shows drought tolerance in Brazil. Unreared larvae from Brazil and Australia allocated to genus Fissimentum are discussed in relation to the type species.

Identification of chironomid larvae often is hampered by incomplete knowledge of the full life history (Epler and Ferrington, 1994). This arises from an historical legacy of species descriptions based on the adult male, which has deterred most taxonomists from naming taxa solely on the imma- ture stages because of the risk of unintentional creation of synonymy with previously described but unreared adults. However, locating and rearing par- ticular larvae to obtain the complete life history for description may be slow. For example, it took nearly half a century between the description of Para- tendipes basidens Townes and the discovery of its distinctive larva (Epler and Ferrington, 1994) and some thirty years for the equally characteristic Stele- chomyia to be fully associated (Reiss, 1982).

Among the distinctive larval forms which have remained unreared for a protracted period is a group of Chironomini that have curious medially cleft menta. First reported from the southern USA and the neotropics by Roback (1966) as "Tendipedini genus A," this taxon encompassed the larvae of four species and one variety. By the time of the compilation of the keys and diag- noses for the Holarctic Chironominae (Finder and Reiss, 1983), the still- unreared taxon (there referred to as "Chironomini genus A Roback") was known to occur in marginal sediments of slowly-flowing, tropical, lowland rivers of South America, Florida and Texas.

In 1993, the junior author found a distinctive larva of this group to be common in potamal benthic habitats of the Rio Bento Gomes, a white water river in the Brazilian state of Mato Grosso. Using both individual and mass techniques, pupae and adults of both sexes were reared and found to belong to no formally described taxon. In this and contemporary studies elsewhere in Brazil a second of Roback's species was found. Meanwhile in Australia larvae apparently belonging also to "Chironomini genus A Roback" were discovered in a dystrophic subtropical perched lake and among an earlier survey collec- tion from the marginal sediments of a temperate river.

' Received August 7, 1995. Accepted September 30, 1995.

2 CSIRO Division of Entomology, Box 1700, ACT 2601, Australia.

- Universidade Federal de Mato Grosso, Cuiaba, MT, Brazil.

ENT. NEWS 107(1): 1-15, January & February, 1996

ENTOMOLOGICAL NEWS

In this contribution we describe the genus as new, bestowing the name Fissimentum based on the distinctive cleft larval mentum. We describe and illustrate the pupa and both sexes of adult, redescribe and illustrate the larvae, examine the phylogenetic position and discuss the ecology, including the lar- val desiccation tolerance.

MATERIALS AND METHODS

Larvae were collected by conventional nets and reared in the laboratory (by Nolle) in petri dishes filled with mud and water from the river and main- tained at ambient temperature (27-32°C). Associated material was preserved in 75% ethanol. Australian material either died in attempted rearing or was preserved directly on collecting. Microscope slide preparation (Cranston) involved clearing where necessary with 10% KOH, neutralization and initia- tion of dehydration with glacial acetic acid, then mounting from propan-2-ol (isopropanol) into Euparal.

Morphological terminology follows Saether (1980) except where we adopt Langton's (1994) suggested use of taenia (adjective taeniate) for "fila- mentous" or "lamelliform" (LS) pupal setae.

All measurements in urn unless stated otherwise.

Fissimentum NEW GENUS

Fissimentum Cranston and Nolle, gen. nov. "Tendipedini Genus A" Roback 1966: 325 "Chironomini Genus A Roback"; Finder & Reiss, 1983: 349; Epler, 1992: 7.116

Type species: Fissimentum desiccatum Cranston and Nolte, sp. nov., by

present designation. Etymology: from L. fissus cleft, past participle of findere - to split and

NL. mentum, the median toothed plate. Neuter noun.

Generic diagnosis

Adult. Medium-sized species, with body length to 5mm, wing length to 2.5mm. Wing unpatterned; thorax brown with darker vittae and postnotum; legs dark brown with yellower basi- tarsomeres.

Antenna. Male with 13 flagellomeres, antenna! ratio (AR) c. 1.7. Female with 5 flagello- meres (Fig. 1), AR c. 0.4.

Head. Eye bare, with bluntly wedge-shaped dorsomedial parallel-sided extension about 6 ommatidia long; in both sexes eyes separated medially by about width of 4-5 ommatidia. Tempo- ral setae of uni-biserial postorbitals merging into verticals; clypeals present. Frontal tubercles absent. Palp 5 segmented, segment 2 globular, segment 4 shorter than 3 and 5; segment 3 with or without 1 sensilla.

Vol. 107, No. 1, January & February, 1996

Figures 1-5. Fissimenturn desiccatum n. gen. n. sp. adult. 1. Female antenna. 2. Male thorax. 3. Male wing. 4. Apex of anterior tibia. 5. Apex of hind tibia and spur of hind tibial comb in lateral view.

ENTOMOLOGICAL NEWS

Thorax (Fig. 2). Antepronotal lobes tapering dorsally, medially narrowly separated. Scutum not overreaching antepronotum; profile of scutum gently rounded, tubercle lacking. Acrostichals biserial running from anterior thorax to mid-scutum; dorsocentrals, prealars and scutellars unise- rial.

Wing (Fig. 3). Membrane without setae, with moderate to strong microtrichiation ('puncta- tion'). Anal lobe rounded. Costa ending abruptly at apex of R4+s, somewhat proximal to wing apex; R2+3 running midway between but ending in proximal V4 between Rj and R.^. FCu slightly distal to RM. R, R[ and R4+5 setose in both sexes. Squama setose.

Leg. Apex of fore tibia with rounded scale, without spur (Fig. 4). Mid and hind tibiae api- cally with two nearly fused combs (Fig. 5) occupying two-thirds circumference of tibial apex, inner comb without spur, outer (longer) comb with short, curved spur (Fig. 5). Fore leg ratio > 2.0. Pulvilli absent. Sensilla chaetica absent. Beard absent.

Abdomen. Tergites I - VII with irregularly scattered setae.

Hypopygium (Fig. 6). Anal tergite bands weak, delimiting median anal tergite setae that intergrade into shorter, finer apical setae. Anal point short, tapering to blunt apex, arising from elevated projecting tergal extension. Superior volsella slightly swollen basally and microtri- chiose/setose, with curved digitiform extension, without microtrichia, with 2 medially directed setae on inner margin. Median volsella absent. Inferior volsella fused to full length of gonocox- ite, extending to apex of gonocoxite; microtrichiose with medially and dorsomedially directed, simple setae, without differentiated posteriorly directed strong seta. Gonostylus bulbous at base, straight, ending bluntly. Sternapodeme bluntly pointed apicomedially, without oral projections. Phallapodeme elongate, narrow.

Female genitalia (Figs. 7-10). Notum long and thin, with long, broadened rami. Gono- coxapodeme almost straight, not fused medially. Coxosternapodeme IX weakly sclerotised and gently curved. Dorsomesal lobe of gonapophysis VIII (Fig. 9) elongate, continuous with inner contour of vagina, microtrichiose except hyaline apico-medially. Ventrolateral lobe distinct, dark- ened, rectangular, as large as dorsomesal lobe (Fig. 10), lying lateral to, and not covering, dor- somesal lobe, microtrichiose basally, with long pointed scales apico-medially. Apodeme lobe more or less rectangular, variably sclerotised, lying dorsal to dorsomesal lobe. Labia hyaline, with microtrichia (Fig. 8). Gonocoxite IX small, not laterally extended, with 1-2 setae. Tergite IX large, undivided. Postgenital plate large, microtrichiose. Seminal capsules oval, darkened near very short neck; seminal ducts straight and ending separately. Cerci relatively small, elongate-quadrate (Fig. 7).

Pupa. Medium-sized, up to 6.5mm long, red colored. Cephalothorax pale to mid-brown, anterior abdominal segments very pale brown, posterior abdomen pale with darker brown apophy- ses, comb and anal lobe.

Cephalothorax. Cephalic area without tubercles, frontal warts or frontal setae. Thorax (Fig. 1 1) with 1 median, 1 lateral taeniate antepronotal seta; 2 stout taeniate precorneals; dorsocentral (dc) 2 midway between dc,, and the more approximated dc3 and dc4, all subequal and rather stoutly taeniate. Thoracic horn very plumose; basal ring (Fig. 12) well developed, oval, with 1 elongate-oval tracheal bundle. Median suture smooth except few scales in mid-thorax. Prealar tubercle absent.

Abdomen (Fig. 13). Tergite I bare, II-VII with subquadrate area of spinules, VII with ante- rior transverse band, VIII with antero-lateral fine spinule area. Anal segment bare. Tergite II hook row continuous, 60% tergite width, comprising c. 50-60 hooks. Conjunctives III/IV and IV/V with fine anterior directed spines/spinules. All sternites with at least anterior transverse band of spin- ules, most strongly developed and extending posterolaterally on I and II. Pedes spurii A present on sternite IV, weak or absent on V and VI; pedes spurii B weak. Posterolateral corner of segment VIII dark, few stout golden-brown teeth (Fig. 14). Apophyses strong.

Vol. 107, No. 1, January & February, 1996

Figures 6-10. Fissimentum desiccatum n. gen. n. sp. genitalia. 6. Male, left side ventral, right side dorsal. 7. Female, lateral. 8. Female, ventral. 9. Dorsomesal lobe of gonapophysis VIII. 10. Ven- trolateral lobe of gonapophysis VIII.

ENTOMOLOGICAL NEWS

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12

13

Figures 11-14. Fissimentum desiccatum n. gen. n. sp. pupa. 11. Thorax, lateral. 12. Base of tho- racic horn. 13. Abdominal tergites. 14. Posterolateral corner of sternite VIII.

Vol. 107, No. 1, January & February, 1996

Setation. Segment I with 2D, IV and without L setae; II-VII with 5D, 2-3V; 3L on II-IV, V- VII with 4L taeniate setae, VIII with OD, 2V, 5 taeniate L setae. 1 pair of 0 setae on tergites and sternites II - VII.

Anal lobe rather elongate, with fringe of 50-1- uniserially inserted taeniate setae, setal bases darkened. Dorsal taeniate seta small. Genital sac of male reaching just beyond apex of anal lobes, female genital sac shorter than anal lobes.

4th instar Larva. Medium sized, up to 9mm long, with ventral head length up to 650 pin, red colored, with dark occipital margin and "collar" lying anterior to lateral occipital mar- gin, giving impression of doubled margin (Figs. 15-16).

Dorsal surface of head (Fig. 17). Frontal apotome broad, without frontal pit; labral sclerite I and 4 disrupted, 2 and 3 complete.

Antenna (Figs. 18, 27, 28). Six segmented, either with short 4th segment or with each suc- cessive segment shorter than the preceding. Lauterborn organs small to moderately well devel- oped and alternate on apices of 2nd and 3rd segments. Segment 3 with subapically inserted fine style or style absent. Ring organ in apical third of segment 1, seta absent. Blade extending beyond antenna apex.

Labrum (Figs. 19, 32). SI plumose, with branching strongest on inner margin; SII long, curved simple; SHI simple, short; SIVa small, SIVb strongly developed. Chaetae developed as 2 broad scales. Seta praemandibularis strong and simple. Labral lamellae broad, with slight indica- tion of median division. Pecten epipharyngis of three separate scales, either simple, narrow, elon- gate and pointed or 3-4 toothed in a single plane. Chaetulae short, triangular or with 4-5 inner teeth; chaetulae basales weak. Premandible with 2 pointed teeth and strong brush.

Mandible (Figs. 20, 29-31). Dorsal tooth absent (in one species perhaps represented by medio-dorsal hooked tooth [Fig. 31]); strong apical tooth and 3 small inner teeth. Pecten mandibu- laris absent. Seta subdentalis broad, sinuous, variably extended up to length of apical tooth. Mola and inner margin smooth. Seta interna absent.

Menturn (Figs. 21-26). With distinct cleft in mid-mentum, with cleft including either paired small teeth, fine serrations or smooth inner surface. Cleft and median teeth combined forming ventromenturn faintly demarcated by antero-median extension of ventromental plate, dorsomen- tum of six teeth on each side, variously organized, sometimes directed antero-medially; all teeth brown. Ventromental plates separated medially by > 50% of menturn width, elongate with smooth margin, with striae either of regularly spaced broad lappets without anterior hooks or spines (Fig. 23) or variably reduced (Fig. 26). Setae submenti very long, simple.

Maxilla broad, with exceptionally long maxillary palp.

Abdomen. Lateral and ventral tubules absent. Anterior parapods with dense, fine claws, some of which may be finely serrate apically; posterior parapod claws simple, some broad-based, with or without basal fine spinules. Procercus weakly pigmented, small, as wide as high, bearing 6-7 subec|ual anal setae. Supraanal setae as long as anal setae, procercal seta elongate, half length of anal and supraanal setae. Four unconstricted anal tubules.

ENTOMOLOGICAL NEWS

15

b

19

20

22

Figures 15-23. Fissirnentum n. gen. n. sp. larva. Lateral head of 15. F. desiccatum. 16. F. sp. 2. F. desiccatum: 17. Dorsal head. 18. Antenna. 19. Labrum. 20. Mandible. 21. Mentum and ven- tromental plates. 22. Median mentum, 23. Detail of striae.

Vol. 107, No. 1, January & February, 1996

Fissimentum desiccation NEW SPECIES

Genus A sp. 4 Roback 1966: 326.

Etymology: from L. desiccare, to dry up, referring to the desiccation tolerance of this species.

Male adult (n=3). Body length 4.7-5.4mm, wing length 1.7-2.0 mm. Brown, with apical 2/3 of tarsomere 1 pale.

Head. With 13-18 uniserial temporal setae, 15-20 clypeals. Antenna with apical flagello- mere 740-890 long, basal 12 flagellomeres 400-445 long, AR 1.73-2.00, palp segment 2-5 lengths: 38-45, 175-195, 145-160, 205-265.

Thorax. Setation: acrostichals 10-16, biserial, dorsocentrals 8-11, uniserial, 3 prealars, 7-8 scutellars.

Wing with VR 1.05-1-07. Vein setation: R with 16-21, R, 8-13, R4+5 12-13; squama with 12-13.

Leg lengths and proportions:

Fe Ti Tal Ta2 Ta3 Ta4

PI 845-935 450-540 1190-1405 865-900 575-610 470-520

PII 785-900 685-790 515- 540 230-258 160-186 105-115

PHI 755-865 755-880 715- 845 355-420 265-320 150-185

Ta5 LR BV SV BR

PI 215-250 2.34-2.60 1.2-1.3 1.1-1.2 0.8-1.2

PII 90-100 0.67-0.68 3.4-3.6 3.1 1.4-2.0

PHI 105-130 0.94-0.96 2.4-2.5 2.1 1.8-2.2

Sensilla chaetica absent.

Hypopygium (Fig. 6). Dorsal tergite IX setae 12-17, bounded laterally by weak tergal bands, 11-14 finer setae on ventral surface of tergite IX. Gonocoxite 220-235 long, gonostylus 80-105 long.

Adult female (n = 4). Body length 4.3-5.4 mm, wing length 1.9-2.3 mm, color as male.

Head. With 13-15 biserial temporal setae, 23-27 clypeals. Antenna with apical flagellomere 126-151 long, basal 4 flagellomeres 330-355 long, AR 0.38-0.42. Palp segment 2-5 lengths: 45- 50, 175-185, 170-185,265-320.

Thorax. Setation: acrostichals 18-20, biserial, dorsocentrals 15-18, uniserial, 3 prealars, 8-9 scutellars. Wing with VR 1.08-1.12; setation: R with 20-23, R, 16-23, R4+5 26-28, squama with 11-23.

10 ENTOMOLOGICAL NEWS

Leg lengths and proportions as follows:

Fe	Ti	Tal	Ta2	Ta3	Ta4
880-980	545-620	1260-1350	900-910	590-610	505-520
870-970	790-880	535- 580	230-250	160-170	105-125

PI PII

PHI 820-900 855-955 755- 790 355-395 285-325 180-190

Ta5 LR BV SV BR

PI 215-240 2.3 -2.4 1.2-1.3 1.1-1.2 0.7-1.1

PII 80-105 0.65-0.69 3.7-3.9 3.1-3.2 1.3-1.5

PHI 125-145 0.83-0.91 2.4-2.7 2.2-2.3 1.9-2.3

Sensilla chaetica absent. Genitalia. As in Figs. 7-10.

Pupa (n = 4) (Figs. 1 1-14). Body length 5.9-7. 2mm. Pale with darker apophyses on more poste- rior abdominal segments. Distance from dcj - dc2 88-94, dc2-dc3 115-122, dc3-dc4 28-38. Hook row on tergite II with 47-55 hooks, occupying 56-60% of the segment width. Anal lobe with 36-40 taeniate setae.

4th instar larva (n = 5) (Figs. 17-23). Body length 5. 7-9. 5mm, deep red pigmented; head capsule length 430-480, pale yellow with brown mentum, pale brown mandible, with characteristically doubled pale occipital margin.

Antennal segment lengths, 53-58, 18-22, 10-12, 1-2, 5-6, 3-4; AR 1.20-1.34; alternate Lauter- born organs 1-2 long; blade length 46-50; style length 10-12.

Mandible length 150-162. Mentum width 88-98, ventromental plate width 140-152. Pre- mandible length 56-66.

Material examined. HOLOTYPE: male, Brazil, Mato Grosso, Rio Bento Gomes, 16°20'S 56°32'W, 1 10m a.s.l., 17.viii. 1994, U. Nolle; deposited in the Entomological Collection of the Federal University of Cuiaba, Mato Grosso, Brazil (UFMT). PARATYPES, 2 males, 4 females, 4 Pe, 11 larvae, same data as holotype, If, IPe, 1L in The Natural History Museum, London (BMNH), 1m, If, IPe, 1L, deposited in Zoologische Staatsammlung Miinchen, Ger- many (ZSM), remainder in Australian National Insect Collection, Canberra (ANIC).

Larval taxa

The following two larval taxa share the cleft mentum with F. desiccatum, but differ from the genotype in the pecten epipharyngis scales, which in both taxa are toothed rather than elongate and simple, and the reduction of the ven- tromental plate striae. However, features of the labrum, the very extended maxillary palp and the mandible shape are all shared, apparently derived fea- tures that suggest homology of the cleft mentum, rather than convergence.

Fissimentum sp.2

Tendipedini Genus A species 2 Roback 1966: 326.

4th instar larva (n = 5). Body length 8-9 mm. Head capsule length 620-660, golden to pale- brown with brown mentum, golden to pale brown mandible, with broad brown "collar" (wide

Vol. 107, No. 1, January & February, 1996

11

Figures 24-32. Fissimentum n. gen., undescribed larvae. Menta of: 24. F. "sp. 2". 25. F. sp. "Aus- tralia". 26. Detail of striae of F. sp. "Australia". Antenna of: 27. F. sp. "2". 28. F. sp. "Australia". Mandible of: 29. F. sp. "2". 30. F. sp. "Australia". 31 detail of mandible of F. sp. "Australia". 32. Labrum of F. sp. "Australia", a. detail of SI seta.

12 ENTOMOLOGICAL NEWS

occipital margin). Antenna (Fig. 27) segment lengths, 55-62, 18-20, 18-20, 4-5, 6- 7, 2-3, AR 1.06-1.18; alternate Lauterborn organs 4-5 long; blade length 80-88; style not visible. Mandible (Fig. 29) length 215-225. Mentum (Fig. 24) width 90-1 10, ventromental plate width 190-230. Labrum with premandible length 84-88.

Material examined. 5L, BRAZIL, Sao Paulo, Sao Carlos, Faz. Cauchim. 22°02S 47°53W, 1993, S. Strixino (1 to UFMT, 3 to ANIC). 5L, BRAZIL, Sao Paulo, Itarapina, Respresa do Lobo, 1979, S. Strixino (1 to Zoologische Staatsammlung Miinchen, 4 to ANIC).

Fissimentum sp. "Australia"

4th instar larva (n=l). Body length unknown (only head capsule retained). Head capsule length 350, pale yellow with brown mentum, pale brown mandible, with doubled occipital margin somewhat darker.

Antenna (Fig. 28) segment lengths, 32, 15, 10, 10, 7, 5; AR 0.68; alternate Lauterborn organs 3-4 long; blade length 56; style 8.

Mandible (Fig. 30) length 106, with strongly developed hooked tooth on dorsal surface (Fig. 31). Mentum (Fig. 25) width 63, ventromental plate width 135. Labrum (Fig. 32) with pre- mandible length 43.

3rd instar larva (n = 2). Body length unknown. Head capsule 260. Antennal segment lengths 18, 1 1, 9, 7, 6, 4, AR c. 0.5, blade 45. Mandible 68. Mentum width 43, ventromental plate width 77. Premandible 27.

Material examined. 2L (1 4th instar, 1 3rd instar), AUSTRALIA, Victoria, Lower Woori Yal- lock, nr Healesville, Yarra River, "YRS 103," 37°46'S 145°31'E, 6.xii.l985, V. Pettigrove (1 to ANIC, 1 to Water Ecoscience, Mt. Waverley, Melbourne, Victoria.), 1L (3rd instar), AUS- TRALIA, Queensland, Fraser Island, Lake Boomanjin, 24°03'S 153°05'E, P. S. Cranston (ANIC).

DISTRIBUTION AND ECOLOGY

The most northerly records of Fissimentum are from coastal plain drainages in southern USA: Lake Murray, S. Carolina (34°N) (Hudson et ai, 1990), the Guadalupe River, Texas (29°N) (Roback 1966) and the Suwannee River, Florida (29°-30°N) (Epler, 1992). The genus occurs in Central Amer- ica (Costa Rica, Epler, 1992), Puerto Rico (L. Ferrington pers. comm.), Peru- vian rivers in the foothills of the Andes (6°S, 1 1°S, Roback, 1966) and as far south as 30°S in the coastal plains of Rio Grande do Sul, Brazil (Wiedenbriig, 1993). In Australia, the two records of the genus span a range from 24° to 37°S.

In the Rio Bento Gomes, a Brazilian intermittent tropical lowland river, the larvae of Fissimentum desiccatum live in the potamal zone. In the studied 6th order stretch, the bed width is 50-60m, and maximum depth 3.5m (except in flood when the river leaves its bed). The discharge is highly dynamic, with 80% of the annual rainfall falling between November and April. With no rain- fall from June to August, sometimes May to September, flow ceases even in the potamal and some drying down takes place. Areas of low current velocity support extensive floating macrophyte beds. During the study period, the tem- perature mean was 28°C (range 21°-31°C), pH mean 6.8 (5.6-7.3), conductiv- ity 80 uS.cm-' (30-130 uS.cnv1).

Vol. 107, No. 1, January & February, 1996 13

The larvae of Fissimentum desiccatum live in soft, muddy sediments including those which include some fine sand but they are not found in pure clay and silt. These sediments may be visibly organically enriched with decomposing macrophytes or litter from the riparian forest, or may contain lit- tle visible organics. Observations through several seasons showed that micro- habitat preference is for the texture of mud, fine sand and detritus, which is prevalent in the dry season when water levels decrease and lentic conditions prevail. Depths range from the littoral (Roback, 1966) to mid-river at 3m. With a maximum density of 4,570 larvae per m2, F. desiccatum may be either the dominant benthic chironomid or share dominance with Polypedilum spp.

The two Australian sites are superficially rather dissimilar: on Fraser Island, Lake Boomanjin is one of the largest perched (elevated above the water table) lakes in the world, with highly dystrophic, claret-colored water of low conductivity (95 uS.cnr1) and low pH (3.5-3.6). The second site, from which a series of larvae was collected, is lightly colored, gently flowing, about 12- 15m wide and several metres deep, in a Yarra River pool disturbed by swim- mers in the summer. However, in both locations the Australian larvae occurred at depths of approximately 1 metre in a fine organic film overlying coarser substrates (Pettigrove, 1988).

DESICCATION

Larvae of Fissimentum desiccatum typically burrow into the sediments, where flimsy silk galleries are formed. When these sediments are dried in the laboratory until cracks form, larval F. desiccatum tolerate desiccation and revive when rehydrated. This ability seems to be related to the distinctive, cel- lophane-like, unwettable larval cuticle. In further testing of this phenomenon (by Nolle), larvae were placed in water-filled petri dishes containing 5-7mm of sediment which were allowed to dry. The duration of exposure to desicca- tion was calculated from the time of loss of visible free water to the time of refilling of the petri dish with water. In the first trial, following three days of dry conditions, pupation and subsequent successful female emergence took place within 36h of rehydration. In a second trial involving several successive desiccations and rehydrations, an initial drying of three larvae for 1 1 h was fol- lowed by completely successful overnight rehydration. These revived larvae were then subjected to different treatments: one was completely dried for 2d - upon rehydration, pupation and the female adult emergence took place within 16h; the two remaining larvae were dried for 36h, rehydrated for lOh, desic- cated again for 3d - upon rehydration, pupation and male adult emergence took place within 19h.

Studies of Polypedilum vanderplancki Hinton have allowed good under- standing of desiccation in larval Chironomidae (Hinton, 1951, 1960a, b). However, this spectacular example of cryptobiosis (loss of all body water and cessation of metabolism) probably is unique and is not repeated in other desiccation-tolerant chironomids. In most other species studied, larval cocoon

14 ENTOMOLOGICAL NEWS

formation is the prevailing mode of survival of drying (Jones, 1975; Grodhaus, 1980; Finder, 1994). On the evidence available, Fissimentum desiccatum does not form a cocoon but may limit water loss through a less permeable cuticle.

SYSTEMATICS

In the Holarctic keys to adult males (Cranston et al., 1989) Fissimentum keys with some difficulty into genera close to Tribelos, differing particularly in the absence of pulvilli. When Holarctic genera with adults lacking pulvilli are considered, then Apedilum and Paralauterborniella enter into considera- tion, but both these genera lack squamal setae and have the fore tibial spur truncate. Never the less, these genera share some larval features with Fissi- mentum, notably the six segmented antennae bearing alternate Lauterborn organs. Looking more widely for resemblance among Chironomini, Fissimen- tum keys in Saether (1977) to the Australian endemic monotypic genus Para- borniella, which lacks pulvilli, has a single spur on comb, and a larva that belongs in the 6 segmented grouping, but the fore tibial spur of this taxon is very flat, and the female genitalia differ strongly. Ignoring the absence of pul- villi, Polypedilum is a candidate, but this is refuted by the immature stages, both pupa and larva.

Features of the pupa are predominantly uninformative of relationships, with those few Holarctic Chironomini taxa that lack frontal setae (such as Robackia) eliminated on other grounds.

In view of this uncertainty, data matrices comprising character states scored from all life history stages of 50 genera of Chironomini have been com- bined and analyzed using the criterion of parsimony, following the rationale of Cranston (1994), with Pseudochironomus and Riethia (Pseudochironomini) chosen as outgroups. The results show Fissimentum postulated to be the sister group to Imparipecten Freeman, a taxon whose full description is in press (Cranston and Hard wick, 1996). These two are closely related to Conochi- ronomus Freeman (Cranston and Hare, 1995) and Skusella Freeman and more distantly to the genera centered on Stictochironomus and Paratendipes. This monophyletic generic grouping is supported almost entirely by the six-seg- mented larval antenna, with all supportive characters from the pupa and adults being highly homoplasious. Provisionally this placement is accepted, pending incorporation of further taxa from the six-segmented larval antenna group, thereby allowing phylogenetic analysis with species treated as terminals (rather than a priori determined genera, as at present).

ACKNOWLEDGMENTS

We are grateful to Susan Strixino for providing specimens of Roback's "species 2" for incorpora- tion in this study, and to Wendy Lee for databasing the Australian specimens into the ANIC data- base. We thank all our colleagues for responding to requests for distributional information, particularly John Epler, Len Ferrington and Professor Ole Sasther. Ole Saether together with Penny Gullan and Jon Martin reviewed the manuscript.

Vol. 107, No. 1, January & February, 1996 15

LITERATURE CITED

Cranston, P.S. 1994. Systematics. pp. 31-61 In: P.D. Armitage, P.S. Cranston and L.C.V. Finder [eds.], Chironomidae: Biology and Ecology of Non-biting Midges. Chapman and Hall, Lon- don, Glasgow, New York, Tokyo, Melbourne, Madras.

Cranston, P. S. and Hare, L. (1995, in press) Conochironomus Freeman: an Afro-Australian Chironomini genus revised (Diptera: Chironomidae). Syst. Entomol. 20:

Cranston, P. S., Dillon, M., Finder, L. C. V. and Reiss, F. R. 1989. Keys and diagnoses of the adult males of the subfamily Chironominae (Diptera, Chironomidae). Entomol. Scand. Suppl. 34: 352-502

Cranston, P.S. and R. Hardwick 1996. The immature stages and phylogeny of Imparipecten Freeman. Aquatic Insects. In press.

Epler, J. H. 1992. Identification Manual for the Larval Chironomidae (Diptera) of Florida. State of Florida Department of Environmental Regulation, Central District, Orlando.

Epler, J. H. and Ferrington, L. C. 1994 The immature stages of Paraten dipes bastdens Townes (Diptera, Chironomidae: Chironominae). J. Kans. Entomol. Soc. 67: 311-7.

Grodhaus, G. 1980. Aestivating chironomid larvae associated with vernal pools, pp. 315 - 22. In Chironomidae. Ecology, Systematics, Cytology and Physiology, D.A. Murray, [ed.]. Perga- mon Press, New York.

Hinton, H. E. 1951. A new chironomid from Africa, the larva of which can be dehydrated with- out injury. Proc. Zool. Soc. London. 121: 371-80.

Hinton, H. E. 1960a. A fly larva that tolerates dehydration and temperatures from - 270°C to + 102°C. Nature. 188:336-7.

Hinton, H. E. 1960b. Cryptobiosis in the larva of Polypedilum vanderplanki Hint. (Chironomi- dae). J. Insect Physiol. 5: 286-300.

Hudson, P. L., Lenat, D. R., Caldwell, B.A. and Smith, D. 1990. Chironomidae of the South- eastern United States: A checklist of species and notes on biology, distribution, and habitat. Fish Wildl Res. 7: 1-46.

Jones, R. E. 1975. Dehydration in an Australian rockpool chironomid larva, Pamborniella ton- noiri. Proc. Roy. Entomol. Soc. London, A Gen. Entomol. 49: 111-9.

Langton, P. H. 1994. If not "filaments," then what? Chironomus. 6: 9.

Pettigrove, V. J. 1988. Biological monitoring of the Yarra River using macroin vertebrates. Envi- ronment Protection Authority, Victoria. Report No. SRS 88/014.

Pinder, L.C.V. 1994. The habitats of chironomid larvae, pp. 107-135 In: P.D. Armitage, P.S. Cranston and L.C.V. Pinder [eds.], Chironomidae: Biology and Ecology of Non-biting Midges. Chapman and Hall, London, Glasgow, New York, Tokyo, Melbourne, Madras.

Pinder, L.C.V. and Reiss, F. 1983. The larvae of Chironominae (Diptera: Chironomidae) of the Holarctic Region - keys and diagnoses. Entomol. Scand. Suppl. 19: 293-435.

Reiss, F. 1982. Hyporhygma n. gen. und Stelechomyia n. gen. aus Nordamerika (Diptera, Chi- ronomidae). Spixiana 5: 289-302.

Roback, S. S. 1966. The Catherwood Foundation Peruvian-Amazon Expedition XII. Diptera, with some observations on the salivary glands of Tendipedidae. Monogr. Acad. Nat. Sci. Phila. 139: 159-209.

Saether, O. A. 1977. Female genitalia in Chironomidae and other Nematocera: morphology, phy- logenies, keys. Bull. Fish. Res. Board Can. 197: 1-211.

Szether, O. A. 1980. A glossary of chironomid terminology (Diptera: Chironomidae). Entomol. Scand. Suppl. 14: 1-51.

Wiedenbriig, S. 1993. Aspectos da estructura espacial da macro fauna bentica da Lagoa Emboaba (RS - Brasil). Masters thesis, Federal University of Rio Grande do Sul (UFRS), Porto Alegre, 157 pp.

16 ENTOMOLOGICAL NEWS

LIFE HISTORY OF THE WEEVIL

EUHRYCHIOPSIS LECONTEI,

A POTENTIAL BIOLOGICAL CONTROL AGENT OF EURASIAN WATERMILFOIL1

S.P. Sheldon2, L.M. O'Bryan3

ABSTRACT: We followed weevil life history in the lab and phenology in the field. In lab cul- tures, weevils progressed from eggs to adults in approximately 30 days. Females laid an average of 1.9 eggs per day; hatching success was 87%. In a Vermont lake, weevil adults and eggs were first found in late May. Thereafter there was a cyclic series of peaks in weevil stage abundance; there appeared to be three generations of weevils each summer in Vermont. This weevil is being evaluated as a possible agent of biological control.

Euhrychiopsis lecontei (Dietz) (Colonnelli 1986), a North American aquatic weevil, has potential as an agent of biological control for Eurasian watermilfoil [Myriophyllum spicatum (L.)]. Eurasian watermilfoil is a nui- sance weed found throughout North America (Couch and Nelson 1986). In laboratory and field trials the weevil had a significant negative effect on Eurasian watermilfoil (Creed and Sheldon 1993), but not on native plants (Sheldon and Creed 1995). In the field in two lakes without weevils, when enclosed with weevils Eurasian watermilfoil did not increase in biomass over the growing season and by the end collapsed, contrary to control plants in enclosures without weevils (Sheldon and Creed 1995). In another lake, wee- vils were associated with an extensive decline of Eurasian watermilfoil (Creed and Sheldon 1995).

This native weevil is feeding on an exotic plant. Prior to the introduction of Eurasian watermilfoil the weevil most likely fed on native Myriophyllums. In Alberta, Canada where Eurasian watermilfoil has not been found, E. lecon- tei was found on northern watermilfoil, Myriophyllum sibiricum Komarov (= exalbescens Fernald) (Creed and Sheldon 1994).

The life history and phenology of this potentially important weevil has not previously been documented.

METHODS

To follow the life history E. lecontei we set up growth chambers in a con- trolled lab setting. We collected < 30 cm long Eurasian watermilfoil stems

1 Received February 15, 1995. Accepted June 2, 1995.

2 Department of Biology, Middlebury College, Middlebury Vermont, 05753 USA.

3 Department of Biological Sciences, University of Santa Barbara, Santa Barbara California,

93106 USA.

ENT. NEWS 107(1): 16-22, January & February, 1996

Vol. 107, No. 1, January & February, 1996 17

from local Vermont lakes and planted them into cups of autoclaved lake sedi- ment then enclosed each in a clear, cylindrical polycarbonate chamber (30 cm long, 6 cm inside diameter). Each chamber was capped with a lid of 202 pm Nitex mesh. The chambers were set in aquaria filled with aerated tap water. Each chamber was also individually aerated. Chambers were housed in a light room, illuminated by artificial light under a 16 h light : 8 h dark regime. Water temperatures ranged from 21.5 - 24.0 °C.

Adult E. lecontei were collected from M. spicatum and placed in the chambers. Within 24 hours after an egg was laid on an Eurasian watermilfoil plant, we transferred the plant and egg into a new chamber, and examined the egg daily until hatching. Each newly hatched larva was transferred to the meristem of an undamaged Eurasian watermilfoil plant in a chamber. Plants were added to the chambers, usually every second or third day, when the plants in the chambers had extensive apical damage. Late instar larvae formed pupal chambers inside plant stems. Plants were handled often, and many stems containing pupae broke.

Because the repeated handling could have affected pupal duration in the lab, we also looked at pupal duration in the field. We put late instar larvae on M. spicatum stems rooted in sediment in a local lake. The larvae and a portion of the plant stem were enclosed in a polycarbonate cylinder (30 cm by 4 cm diameter). The ends of the chambers were capped with foam to prevent wee- vil escape and allow air exchange. The dates of initiation of pupal phase and adult emergence were recorded.

In the lab, each newly emerged adult was removed from its chamber. Weevil sex could be determined by the shape of the pygidium: flat (female) or knobbed (male) (C. O'Brien, Florida A. and M. University, Tallahassee Florida, personal communication). For quantification of the lifetime egg pro- duction by a female, we placed each newly emerged female in a chamber with two males and from three to six M. spicatum stems with intact meristems. Plants were replaced when there was extensive feeding damage or there were many (>5) eggs per meristem. Dead males were replaced. The number of eggs each female laid was recorded every 3-4 days until she died.

To see whether weevils could survive on a different genetic stock of Eurasian watermilfoil we set up a batch culture in the lab. Weevils were placed in an aquarium containing M. spicatum collected from Lake Minnetonka, Min- nesota, USA. The Eurasian watermilfoil in Lake Minnetonka is gentically dif- ferent from Vermont Eurasian watermilfoil (G. R. Furnier, University of Minnesota, St. Paul MN, personal communication).

To determine if weevils could live on native watermilfoil, weevils were collected from M. spicatum, and placed in an aquarium with the native north- ern watermilfoil, Myriophyllum sibiricum. We followed both of these cultures qualitatively, noting adult survival, deposition of eggs on plants, and evidence of tunneling damage by weevil larvae.

18 ENTOMOLOGICAL NEWS

E. lecontei phenology was followed in Lake Bomoseen, VT during the summers of 1991-1994. At three sites, transect lines were set up running per- pendicular to the shore. On each transect, the upper 40 cm of 10 plants were collected. Plants were taken at regular intervals over the transect line, and three lines were run at each site; n = 90 stems per date. Plants were examined under a dissecting microscope; all weevils were removed and counted. In 1991 collection started in early July. In 1992, and subsequent years, samples were started in April, with weevils first being collected in mid-May. M. spicatum apical shoots were collected weekly from in 1991 and 1992, and every third week in 1993 and 1994.

RESULTS AND DISCUSSION

In the laboratory, eggs were laid on apical meristems. Eggs were ellipti- cal, approximately 0.52 (± 0.06, mean ± SE) mm long and 0.39 (± 0.05) mm wide (n = 36). First instar larvae fed on meristematic tissue for 3-5 days. Later instar larvae spent most of their time inside the stem, resulting in a hollowed- out stem. Sometimes, particularly when larvae reached the end of an intern- ode, larvae burrowed out, spiraled across the outside of a stem to a new internode, then burrowed back into the stem. Larvae were usually found in the top third of the plant. Late instar larvae were up to 4.5 mm long. Puparia were formed inside the stem and tended to be found further down in thicker (> 4 mm) portions of the stem. Adults were small, typically between 2 and 3 mm (2.85 ± 0.88 mm, n = 35) from the anterior edge of the eye to posterior end of the pygidium, and were usually found on the top third of the plants, where they fed on both leaves and stem tissue. In the lab, all of the life history stages took place entirely under water.

Under these laboratory conditions with temperature ranging from 2 1 .5 to 24°C), the duration of the egg phase was 3.9 (± 0.2, n = 48) days. Larval dura- tion averaged 13.0 (± 1.8, n = 9) days. Pupal duration in the lab averaged 13.0 (± 1.5, n = 5) days. The sum of these values suggests that the average time between egg deposition and emergence as an adult is approximately 30 days. Mean pupal duration on rooted plants in the field was 9.6 (± 1.2, n = 24) days, reducing the estimate from egg to egg as 26 days.

Because it was difficult to get weevils through the pupal phase, we had only 7 unmated females for which we knew the date of emergence. Total egg production for these females ranged from 3 to 562 eggs per female with a mean of 1 .9 (± 0.4) eggs laid per female per day. Eggs were preferentially laid on the apical meristem. If eggs were already present on the apical meristem, eggs were often laid on the uppermost lateral meristems or on leaves near the plant apex. Hatching rate of eggs was 87.3%. Normally a few eggs were laid on each meristem in a chamber, however in a concurrent experiment under similar conditions, when weevils were enclosed with few plants, we found as

Vol. 107, No. 1, January & February, 1996 19

many as 29 eggs on a single plant. In the lab, female length of life as an adult ranged from 11 to 162 days.

For the batch culture of weevils with M. spicatum from Minnesota, larvae and adult weevils from Vermont fed on the Minnesota plants, and eggs were laid and hatched. In the batch cultures of the native watermilfoil M. sibiricum, adults fed on the plants and eggs were laid. Qualitatively, there were fewer adults generated from the native watermilfoil batch cultures than from Eurasian watermilfoil from Minnesota.

The life history data collected in the laboratory are consistent with our observations of E. lecontei phenology in the field (1991-1994); time from egg to egg was about 26 days, which could yield three generations of weevils each summer. In Lake Bomoseen there appear to be three generations of weevils each summer. The abundance of each life stage was cyclic (Figure 1). In the spring the first weevils collected were adults, then eggs. Peaks in egg abun- dance were followed by increased larval densities, followed by peaks in the abundance of pupae and adults. Thus, although the sample sizes were low in some cases for quantifying length of life history stage, the prediction for dura- tion from egg to egg from lab data was 26 days, similar to what we found in Lake Bomoseen.

In September, densities of weevil eggs declined, followed by a decline of larvae, then pupae, then adults. Thereafter no weevils were found in the lake. Adults appear to overwinter terrestrially in leaf litter along lake margins (C. O'Brien, Florida A. and M. University, Tallahassee Florida, personal commu- nication). Adults have been collected in sweeps of shoreline vegetation in the fall (David Ragsdale, University of Minnesota, St. Paul MN, personal com- munication). We found one adult weevil in terrestrial soil samples collected in October, five meters inland from the edge of Lake Bomoseen.

The patterns of egg laying and adult and larvae location in the field, were also consistent with the lab studies. Weevil eggs were found primarily on the apical or other meristems nearest to the water surface. If there were few meris- tems available, eggs were found on any meristem, or apical leaves. Larvae were usually found in the top meter of the plant. Pupae were typically found further down the stem (>0.5 m) where the stem is thicker (> 4 mm). Adults were usually found on the top one meter of plant.

The current range of the weevil in North America is not well known. E. lecontei previously had been found in Iowa, Michigan. Wisconsin, Alberta, British Columbia, and Saskatchewan (O'Brien and Wibmer 1982). We have found weevils in Connecticut, Massachusetts, New York, and Vermont. E. lecontei have also been found in Minnesota (Newman and Maher 1995) and they have recently been collected in Illinois (M. Pfister, Lake County Health Department, Chicago, IL, personal communication). Creed found weevils on northern watermilfoil, M. sibiricum, in western Washington (Creed and Shel- don 1994).

20

ENTOMOLOGICAL NEWS

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Figure 1. Phenology of weevil life history stages in a Vermont lake. Data are from A. 1991 and B. 1992. Patterns of frequency of life history stages were similar in 1993 and 1994.

Vol. 107, No. 1, January & February, 1996 21

E. lecontei may be a suitable agent for the biological control of Eurasian watermilfoil. Weevils have a significant negative effect on M. spicatum. At the same time, weevils did not have a significant impact on native plant species (Sheldon and Creed 1995). Other insects found in North America have been evaluated as potential biological controls for Eurasian watermilfoil including a moth [Acentria ephemerella (Dennis & Schiffermuller; Painter and McCabe 1988)], another weevil (Phytobius leucogaster Marsham; Buckingham and Bennett 1981), and a midge (Cricotopus myriophylli (Oliver; Kangasniemi and Oliver 1983, MacRae et al. 1990, Kangasniemi et al. 1993). E. lecontei may be a more effective biological control agent because they have a rela- tively long lived feeding adult phase, unlike A. ephemerella (Buckingham and Ross 1981) and C. myriophylli Kangasniemi et al. 1993) facilitating culturing; they are specific to Myriophyllums unlike A. ephemerella (Buckingham and Ross 1981), their phenology is well timed, unlike C. myriophylli (Kangas- niemi et al. 1993); and E. lecontei causes significant damage to the apical submersed portion of the plants, unlike P. leucogaster which feed primarily on flowers (Buckingham and Bennett 1981).

If E. lecontei is used as a biological control agent, it should be noted that all life history stages remain in the apical portion of the plants. Aquatic weed harvesting, a common control technique for Eurasian watermilfoil, removes the top 1-2 m of the plants.

While use of a native insect for biological control of an exotic plant is unusual, it may prove efficient and pose fewer potential drawbacks than intro- ducing an exotic biological control agent. M. spicatum has a similar life his- tory and phenology as native watermilfoils. Presumably this native weevil is coevolved with the native watermilfoils, which decreases the probability of damage to non-target plant species. The weevil coexists with M. sibiricum in both the United States and Canada.

ACKNOWLEDGMENTS

Our thanks to Rob Creed, Ray Newman, and Holly Crosson for reviewing an earlier itera- tion of this paper, two anonymous reviewers and to a pile of undergraduates who helped with the most tedious tasks. This work was Funded by the EPA Clean Lakes Demonstration Program, the U.S. Army Corps of Engineers' Waterways Experiment Station and the Vermont Department of Environmental Conservation.

22 ENTOMOLOGICAL NEWS

LITERATURE CITED

Buckingham, G. R. and C. A. Bennett. 1981. Laboratory biology and behavior of Litodactylus leucogaster a Ceutorhynchine weevil that feeds on watermilfoils. Ann. Entomol. Soc. Amer. 74:451-458.

Buckingham, G. R. and B. M. Ross. 1981. Notes on the biology and host specificity of Acentria nivea = Acentropus niveus. J. Aquat. Plant Manag. 19:32-36.

Colonnelli, E. 1986. Checklist of the Phytobiini of world, with a key to the genera and descrip- tion of a new species from South Africa (Coleoptera, Curculionidae, Ceutorhynchinae). Fragm. Entomol. Roma, 19:155-168.

Couch, R. and E. Nelson. 1986. Myriophyllum spicatum. Pages 8-18 in Proceedings, First Inter- national Symposium on watermilfoil (Myriophyllum spicatum) and Related Haloragaceae Species. Aquat. Plant Manag. Soc., Vicksburg, MS, USA.

Creed, R. P. Jr. and S. P. Sheldon. 1993. The effect of feeding by a North American weevil, Euhrychiopsis lecontei, on Eurasian watermilfoil (Myriophyllum spicatum). Aquat. Bot. 45:245-256.

Creed, R. P. Jr. and S. P. Sheldon. 1994. Aquatic weevils (Coleoptera: Curculionidae) associ- ated with northern watermilfoil (M\rioph\llum sibiricum) in Alberta Canada. Entomol. News 105:98-102.

Creed, R. P. Jr. and S. P. Sheldon. 1995. Weevils and watermilfoil: did a North American herbivore cause the decline of an exotic plant? Ecol. Appl. 5: 1113-1121.

Kangasniemi, B. J. and D. R. Oliver. 1983. Chironomid (Diptera) associated with Myriophyl- lum spicatum in Okanagan Valley lakes, British Columbia. Canad. Entomol. 1 15: 1545-1546.

Kangasniemi, B., H. Speier, and P. Newroth. 1993. Review of Eurasian watermilfoil biocontrol by the milfoil midge. Pages 17-22. In Proceedings, 27th Annual Meeting, Aquatic Plant Con- trol Research Program. Misc. Paper A-93-2. U.S. Army Engineer Waterways Exper. Stat., Vicksburg, MS, USA.

MacRae, I. V., N. N. Winchester and R. A. Ring. 1990. Feeding activity and host preference of the milfoil midge, Cricotopus myriophylli Oliver (Diptera: Chironomidae). J. Aquat. Plant Manag. 28:89-92.

Newman, R. M. and L. M. Maher. 1995. New Records and distribution of aquatic insect herbi- vores of watermilfoils (Haloragaceae: Mvriophvllum (spp.) in Minnesota. Entomol. News 106:6-12.

O'Brien, C. W. and G. J. Wibmer. 1982. Annotated checklist of the weevils (Curculioidae sensu lato) of North America, Central America and the West Indies. Mem. Am. Entomol. Inst. # 34.

Painter, D. S. and K. J. McCabe. 1988. Investigation into the disappearance of Eurasian water- milfoil from the Kawartha Lakes. J. Aquat. Plant Manage. 26:3-12.

Sheldon, S. P. and R. P. Creed Jr. 1995. Use of a native insect as a biological control for an introduced weed. Ecol. Appl. 5: 1122-1132..

Vol. 107, No. 1, January & February, 1996 23

CENTRAL AMERICAN TORTOPUS

(EPHEMEROPTERA: POLYMITARCYIDAE):

A UNIQUE NEW SPECIES AND

NEW COUNTRY RECORDS1'2

C. R. Lugo-Ortiz, W. P. McCafferty3

ABSTRACT: Tortopus bellus, new species, from Costa Rica is described on the basis of the male adult. The species is distinguished by its basally fused penes, undeveloped parastyli, and general abdominal coloration. Tortopus unguiculatus, previously known in Central America from Costa Rica and Nicaragua, is newly reported from Guatemala and Honduras.

The Pan-American mayfly genus Tortopus Needham and Murphy (Polymitarcyidae) is known from 1 1 described species. Seven are from South America (Hubbard and Peters 1981, Domfnguez 1985, Hubbard el al. 1992), three from North America (McCafferty 1975, 1994; Edmunds et al. 1976), and one from South and Central America (Maes 1988, McCafferty and Lugo-Ortiz 1992). Only the North American T. incertus (Traver) is known from larvae and male and female adults (McCafferty 1975, 1994; Edmunds et al. 1976). Of the other described species, three are known from male adults, four from female adults, and two from male and female adults (Traver 1950, Edmunds etal. 1976, Hubbard et al. 1992). Ulmer (1932, 1942) and Traver (1950) pro- vided taxonomic treatments of the adults of the genus. Scott et al. (1959) described the larval stage and its habitat. McCafferty (1975) provided a pro- visional species key to the larvae in North America based on geographic dis- tribution. Until more associations of sexes and of larvae and adults are performed the taxonomy of the genus will remain problematic.

Tortopus is a sister lineage of the Pan-American genus Campsurus Eaton (McCafferty 1991), and they are very similar in both the larval and adult stages. Larvae of Tortopus can be distinguished by the presence of a single subapical tubercle on the medial margin of the mandibular tusks, and the adults by the presence of genital parastyli (males) and parastyli receptors (females) and shriveled and stringlike mid- and hindlegs [see Edmunds et al. (1976): Figs. 33, 206, 207, and 349; McCafferty and Bloodgood (1979): Figs. 1-9]. Larvae of Campsurus possess prominent basal and subbasal tubercles on the medial margin of the mandibular tusks, and adults lack genital parastyli

1 Received July 29, 1995. Accepted August 18, 1995.

2 Purdue Agricultural Research Program Journal No. 14731.

3 Department of Entomology, Purdue University, West Lafayette, IN 47907.

ENT. NEWS 107(1): 23-27, January & February, 1996

24 ENTOMOLOGICAL NEWS

and parastyli receptors and have highly atrophied, short, flattened mid- and hindlegs [see Edmunds et al. (1976): Figs. 350 and 351].

McCafferty et al. (1992) hypothesized that Tortopus has a Neotropical center of origin based on its close relationship with Campsurus. They indi- cated that the restriction of Tortopus to the east in North America was atypi- cal of other Pan-American genera in North America. Tortopus evidently penetrated the Nearctic via the maritime corridor of the Gulf of Mexico rather than via the mountainous corridors used by western genera. The genus appears to be warm-water sublimited, but it is also humid restricted (McCafferty 1975, McCafferty et al. 1992).

Only T. unguiculatus (Ulmer) has been reported from Central America (Maes 1988). We herein describe a new species from Costa Rica and provide new distributional records for T. unguiculatus. The materials studied are housed in the Purdue Entomological Research Collection, West Lafayette, Indiana.

Tortopus bellus Lugo-Ortiz and McCafferty, NEW SPECIES

Figs. 1-2

Male adult. Body length: 8.3 mm; wing: 10.5 mm; caudal filaments: 28.0 mm. Head: Dor- sal surface heavily suffused with purplish gray dots anteriorly, light brown to pale posteriorly, light brown ventrally. Ocellar bases black. Scapes stippled with purplish gray dots, inner sides pale; pedicels entirely suffused with purplish gray dots; flagella pale. Thorax: Pronotum purplish gray anteriorly and posteriorly; heavily suffused with purplish gray dots medially, becoming pale brown laterally; thin pale dorsal median line present. Prosternum pale brown and suffused with purplish gray dots. Mesonotum light brown, posteriorly suffused with purplish gray dots. Meso- sternum heavily suffused with purplish gray dots submedially. Metanotum pale brown, heavily suffused with purplish gray dots medially. Region between costal and subcostal veins in fore- wings lightly suffused with purplish gray from base to middle of wing. Legs suffused with pur- plish gray dots; foretibiae almost black. Abdomen (Fig. 1): Tergum 1 purplish gray and very narrow; terga 2-7 anteriorly pale, becoming heavily suffused with purplish gray dots posteriorly and laterally, and with oblique pale sublateral dashes; terga 8-9 purplish gray, tergum 8 almost twice length of any tergum between terga 2-7; tergum 10 lightly suffused with purplish gray dots. Prominent pleural folds on segments 2-7, suffused with purplish gray dots and marginally pale. Sternal coloration as in terga, except lighter and marginally pale on sterna 2-7. Genitalia (Fig. 2) with bladelike penes, narrowly sclerotized along lateral margin, and basally fused; styli purplish gray, clublike, with very small spines along interior margin, spination becoming more dense dis- tally and forming terminal pad [see McCafferty and Bloodgood (1989): Figs. 3-4]; parastyli unde- veloped. Caudal filaments pale; terminal filament appearing 4-segmented, clublike, suffused with purplish gray dots; cerci very long, with tuft of fine setae distally.

Female adult. Unknown. Larva. Unknown

Vol. 107, No. 1, January & February, 1996

25

Material examined. Holotype: Male adult, COSTA RICA, Heredia Prov., light trap, rain forest, Vlll-24-1987, D. Brigham.

Etymology. The specific epithet is a Latin word meaning beautiful.

Figs. 1-2. Tortopus bellus, NEW SPECIES, male adult: 1. Abdomen (dorsal). 2. Genitalia (ventral).

26 ENTOMOLOGICAL NEWS

DISCUSSION

Tortopus bellus can be distinguished from other members of the genus by its unique abdominal coloration (Fig. 1), basally fused penes, and undeveloped parastyli (Fig. 2).

McCafferty and Bloodgood (1989) indicated that the parastyli probably function as holding structures during copulation. However, the undeveloped nature of these appendages in T. bellus suggests that they could not function in holding the female during copulation, and it is possible that they are vesti- gial in this species. If this is indeed the case, we expect the female of T. bel- lus to have a reduced or no parastyli receptors on abdominal segment 8 [see McCafferty and Bloodgood (1989): Figs. 6-9], a condition which has not been documented in any of the species known from females only.

The undeveloped nature of the parastyli of T. bellus may alternatively indicate a primordial condition of a primitive species of Tortopus. All other species of Tortopus known from males possess elongate parastyli [see Edmunds et al. (1976): Figs. 206 and 207], but the undeveloped nature of the parastyli in T. bellus is more reminiscent of the condition found in Campsurus.

Tortopus unguiculatus (Ulmer)

Material examined. GUATEMALA, Rio Polochic, 111-22-1906, male adults; Panzos, IV-1905, male and female adults. HONDURAS, Gracias a Dios Prov., Rio Sigre, 111-24-29-1952, R Greenfield, male adult.

DISCUSSION

Tortopus unguiculatus was previously reported from Costa Rica (Ulmer 1942) and Nicaragua (Maes 1988). The new records provided herein extend its known range northward. The species probably also occurs in Panama, since it has been reported from Colombia (Ulmer 1920).

Ulmer (1920) originally described this species from male adults. Later, Ulmer (1942) described the female adults. Its larvae, however, remain unknown. Ulmer (1942) indicated that until the male adults of T. igaranus Needham and Murphy are known, the species status of T. unguiculatus should be regarded as tentative.

Vol. 107, No. 1, January & February, 1996 27

ACKNOWLEDGEMENTS

We thank Boris C. Kondratieff (Colorado State University, Fort Collins) for the donation of the material of T. bellus. We also thank Arwin Provonsha (Purdue University, West Lafayette, IN) for the drawings.

LITERATURE CITED

Dominguez, E. 1985. El genero Tortopus Needham y Murphy (Ephemeroptera: Polymitarcydae [sic]) en la Argentina. Physis 43: 69-72.

Edmunds, G. F., Jr., S. L. Jensen, and L. Berner. 1976. Mayflies of North and Central America. Univ. Minn. Press, Minneapolis.

Hubbard, M. D. and W. L. Peters. 1981. Ephemeroptera. Pp. 55-63. In: Aquatic biota of tropi- cal South America, Part 1: Arthropoda, S. H. Hurlbert, G. Rodriguez, and N. D. Santos (eds.). San Diego Univ. Press, California.

Hubbard, M. D., E. Dominguez, and M. L. Pescador. 1992. Los Ephemeroptera de la Republica Argentina: un catalogo. Rev. Soc. Entomol. Argent. 50: 201-240.

Maes, J. M. 1988. Catalogo de los Ephemeroptera y Plecoptera de Nicaragua. Rev. Nica. Ento- mol. 2: 49-50.

McCafferty, W. P. 1975. The burrowing mayflies (Ephemeroptera: Ephemeroidea) of the United States. Trans. Am. Entomol. Soc. 101: 447-504.

McCafferty, W. P. 1991. Toward a phylogenetic classification of the Ephemeroptera (Insecta): a commentary on systematics. Ann. Entomol. Soc. Am. 84: 343-360.

McCafferty, W. P. 1994. Distributional and classificatory supplement to the burrowing mayflies (Ephemeroptera: Ephemeroidea) of the United States. Entomol. News 105: 1-13.

McCafferty, W. P. and D. W. Bloodgood. 1989. The female and male coupling apparatus in Tortopus mayflies. Aquat. Insects 11: 141-146.

McCafferty, W. P. and C. R. Lugo-Ortiz. 1992. Registros nuevos y notas sobre los Ephe- meroptera de Nicaragua. Rev. Nica. Entomol. 19: 1-7.

McCafferty, W. P., R. W. Flowers, and R. D. Waltz. 1992. The biogeography of Mesoameri- can mayflies. Pp. 173-193. In: Biogeography of Mesoamerica: proceedings of a symposium, S. P. Darwin and A. L. Welden (eds.). Tulane Univ. Stud. Zool. Bot., Suppl. Publ. 1.

Scott, D. C., L. Berner, and A. Hirsch. 1959. The nymph of the mayfly genus Tortopus (Ephemeroptera: Polymitarcidae). Ann. Entomol. Soc. Am. 52: 205-213.

Traver, J. R. 1950. Notes on Neotropical mayflies. Part IV. Family Ephemeridae (continued). Rev. Entomol. (Rio de Janeiro) 21: 593-614.

Ulmer, G. 1920. Neue Ephemeropteren. Archiv. Naturg. 85: 1-80.

Ulmer, G. 1932. Bemerkugen ueber die seit 1920 neu aufgestellten Gattungen der Ephe- meropteren. Stett. Entomol. Zeit. 93: 204-219.

Ulmer, G. 1942. Alte und neue Eintagsfliegen (Ephemeropteren) aus Siid- und Mittleamerika. Stett. Entomol. Ziet. 103: 98-128.

28 ENTOMOLOGICAL NEWS

A NEW SPECIES OF NADLERIA

(PSOCOPTERA: LACHESILLIDAE)

FROM THE TAMBOPATA RESERVED ZONE,

MADRE DE DIOS, PERU1

Alfonso Neri Garcia Aldrete^

ABSTRACT: A new species of Nadleria from the western edge of the Amazon Basin, in south- eastern Peru, is here described. It is close to N. mockfordi and it is the second species of the genus known from both sexes; the male of the new species can be separated from the male of N. gamma on details of terminalia, particularly of the epiproct, clunium and phallosome. The types are deposited in the Smithsonian Institution, Washington, D.C.

RESUMEN: Se describe aqui una nueva especie de Nadleria de la Zona Reservada de Tambopata, en la Amazonia Peruana. La nueva especie es cercana a N. mockfordi y es la segunda especie del genero de la que se conocen los dos sexos; el macho de la nueva especie puede separarse del macho de AT gamma en detalles genitales, particularmente del epiprocto, clunio y falosoma. Los tipos de la nueva especie estan depositados en el Smithsonian Institution, de Washington, D.C., U.S.A.

The three known species of the psocid genus Nadleria (N. alpha Badon- nel and Garcia Aldrete, N. mockfordi Badonnel and Garcia Aldrete, and N. gamma Mockford), are virtually restricted to the Amazon Basin; only the for- mer occurs outside of this area, in Trinidad (Badonnel and Garcia Aldrete, 1979, 1980; Mockford, 1985). The purpose of this paper is to describe an addi- tional species of Nadleria from the southwestern edge of the Amazon Basin, in the Tambopata Reserved Zone, Peru. The specimens studied were collected by the team that conducted the Smithsonian Institution Canopy Fogging Pro- ject headed by Dr. Terry L. Erwin. For details of the collecting technique and about the area see Erwin, 1983, 1984, and 1989. The specimens for micro- scopic study were dissected in 80% alcohol and the head, right wings and legs, and terminalia were permanently mounted, either in Euparal or in Balsam of Canada. The measurements are in microns and were taken with a filar microm- eter whose measuring unit was 1.36 microns for wings and 0.53 microns for other parts. The following abbreviations are used for parts measured: FW: fore wing length; HW: hind wing length; F, T, tl, t2: length of femur, tibia and tar- someres of right hind leg; cttl: number of ctenidia on tl; P4: length of fourth maxillary palpomere; fl...fn: length of antennal flagellomeres; 10:

1 Received June 25, 1995, Accepted July 5, 1995.

2 Institute de Biologi'a, UNAM., Departamento de Zoologia, Apartado Postal 70 - 153, 04510, Mexico, D.F. MEXICO.

ENT. NEWS 107(1): 28-32, January & February, 1996

Vol. 107, No. 1, January & February, 1996 29

minimum distance between compound eyes; D: antero-posterior diameter of compound eye; d: transverse diameter of compound eye: PO= d/D (10, D and d, measured in frontal view of head mounted on slide.)- Other abbreviations: M= male, F= female. The types of the species here described will be deposited in the Smithsonian Institution Collection, Washington, D.C.

Nadleria mariateresae Garcfa Aldrete, NEW SPECIES

Figs. 1 - 9

FEMALE. Color (in 80% alcohol). Body reddish brown. Compound eyes black, ocelli clear, with well developed, ochre centripetal crescents. Antennae and legs pale brown, areas next to dorsal articulations of coxae reddish brown, much more pigmented than rest of the leg. Fore wings with large, cloudy brown area covering proximal half of the wing; hind wings hyaline, with slight brown wash along anterior wing margin, from wing base to end of vein Rl, fading posteri- orly. Abdomen pale brown, with small, transverse sclerites on segments 2-7.

Morphology. Vertex of head extended above compound eyes, impressed in the middle; ocelli close together. Fore wing with extensive ciliation in the membrane of the pigmented prox- imal half; veins ciliated, except along Cu2. Hind wing lacking ciliation. Hind tibiae with row of ctenidobothria along median margin reaching distal end; these ctenidobothria not perpendicular to longitudinal axis of tibia. Subgenital plate (Fig. 9), wide, setose, with median lobe slightly pro- jected posteriorly; pigmented area deeply cleft anteriorly, without macrosetae, and with a small, slender, hyaline area in apex of median lobe. Gonapophyses (Fig. 6) slender at base, each with a large pre-apical bulge, ending in a small conical apophysis. Ninth sternum (Fig. 6) with a large, distinct, pigmented transverse area as illustrated. Paraprocts (Fig. 7) elongate, semi-elliptical; sen- soria with 11-12 trichobothria, one, on outer edge, without basal rosette; setae and pigmented area as illustrated. Epiproct (Fig. 8) straight anteriorly, rounded posteriorly, with setal field towards posterior margin, 4 setae much longer than the others, disposed as illustrated.

Measurements. FW: 1743; HW: 1343; F: 355; T: 629; tl: 199; t2: 106;cttl: 14; P4: 87; fl: 155; f2: 128; f3: 112; f4: 92; f5: 58; f6: 60; 10: 337; D: 192; d: 93; IO/D: 1.75; PO: 0.48

MALE. Color (in 80% alcohol). Same as the female.

Morphology. Vertex of head more deeply impressed than that of the female. Hypandrium (Fig. 3) small, triangular, with claspers fused to its sides, each clasper terminating in a straight, finger like projection. Phallosome apodemes fused to form a straight baculum that divides distally, each arm terminating in a pigmented membranous area, these connected by a pigmented U-shaped arch. Clunium (Fig. 2) limited anteriorly by a pigmented area on each side of epiproct, to which each paraproct is articulated. Paraprocts (Fig. 4) with sclerotized, aquiline prong on median mar- gin; areas next to prong and surrounding sensoriuin strongly sclerotized, a mesal pigmented spot next pigmented areas of prong and sensorium, this with 12 trichobothria, one, on outer edge, with- out basal rosette. Epiproct (Fig. 2) with two stout, long, acuminate processes, (one shorter than the other in one specimen).

Measurements. FW: 1839; HW: 1388; F: 362; T: 642; tl: 204; t2: 96; cttl: 15; P4: 91; fl: 181; f2: 143; f3: 123; f4: 94; 10: 332; D: 208; d: 92; IO/D: 1.59; PO: 0.44

30

ENTOMOLOGICAL NEWS

0.5

Figures 1-5. Nadleria mariateresae n. sp. Male. Fig. 1. Fore and hind wings. Fig. 2. Clunium and epiproct. Fig. 3. Hypandrium and phallic apodemes. Fig. 4. Right paraproct. Fig. 5. Frontal view of head. Scales in mm. Figs. 2 and 3 to scale of Fig. 4

Vol. 107, No. 1, January & February, 1996

31

TYPE MATERIAL. PERU. Madre de Dios. Rio Tambopata Reserved Zone. 30km (air) SW Puerto Maldonado, 290m, 12°50' S: 69° 20' W. 6. IX. 1984, holotype M. allotype F, 1 paratype M. 12.XI.1983, 1 paratype M. 25.11. 1984, 1 paratype F. 7. V. 1984, 3 paratypes F. T.L. Erwin et at. collectors; Smithsonian Institution Canopy Fogging Project. Types deposited in the Smith- sonian Institution Collection, Washington, D.C.

The species here described is dedicated to my wife Maria Teresa, who, in many ways, has contributed to my work.

/

/ •>'..•••••••...„•• •'•.«•/:/-<£•' .'" \-Jv- *.\ ;•••*••

i^u^i^li

* Wf-"'''-'-""^-- •«*'* -—*- '"•^••'•^••'i -

^^•^v^- i^1^

0.2

Figures 6-9. Nadleria mariateresae n. sp. Female. Fig. 6. Gonapophyses and ninth sternum. Fig. 7. Right paraproct. Fig. 8. Epiproct. Fig. 9. Subgenital plate. Scale in mm. All figures to the same scale.

With the above description, Mockford's key to the species of Nadleria (Mock- ford, 1985) is modified as follows:

Key to the species of Nadleria (Females)

1. Posterior margin of subgenital plate decidedly protruding posteriorly as a rounded lobe; third valvula with apex projecting as a short process beyond a broad lateral bulge 2

1'. Posterior margin of subgenital plate at least slightly depressed between slightly developed lateral lobes, third valvula with a broad, rounded or somewhat tapering apex, lacking a lateral bulge 3

32 ENTOMOLOGICAL NEWS

2. Rounded lobe of subgenital plate narrow, strongly projected posteriorly; several macrosetae on field of pigmented area of subgenital plate; pigmented area on ninth sternum, between third valvulae, with two sclerotized bands on anterior edge, one to each side of longitudinal midline N. mockfordi Badonnel and Garcia Aldrete

2'. Rounded lobe of subgenital plate broad, slightly projected posteriorly; macrosetae on field

of pigmented area of subgenital plate not apparent; pigmented area on ninth sternum,

between third valvulae, biconcave in the middle, without anterior, sclerotized bands

N. mariateresae n. sp.

3. Subgenital plate only slightly depressed on posterior margin between lateral lobes; third valvula evenly rounded on median margin .... A', alpha Badonnel and Garcia Aldrete

3'. Subgenital plate decidedly depressed on posterior margin between lateral lobes; third valvula decidedly bulging on median margin near apex N. gamma Mockford

DISCUSSION

On female characters, N. mariateresae n. sp. is closer to N. mockfordi Badonnel and Garcia Aldrete than to the other two species in the genus; they have in common projected subgenital plates, paraprocts similarly pigmented, and gonapophyses bulging, with apices projecting into short, conical processes. I would predict the structural characters of the male of the latter species to be similar to the male of N. mariateresae. This and the male of N. gamma can be clearly separated on details of terminalia: in the latter, the phal- lic apodemes widely diverge posteriorly and the epiproct has a single, short, truncate process. The male terminalia of N. mariateresae is strikingly similar to the male terminalia of Lachesilla species in the pedicularia group, occur- ring in South America, as discussed by Mockford (1985).

ACKNOWLEDGMENTS

I wish to thank Terry L. Erwin and Gary F. Hevel, Smithsonian Institution, Washington, D.C., for the loan of specimens from the Rio Tambopata Reserved Zone (ANTSE program).

LITERATURE CITED

Badonnel, A., et A.N. Garcia Aldrete. 1979. Nadleria, un nouveau genre de Lachesillidae (Pso-

coptera) du Bresil. Nouv. Rev. Ent. 9: 3-8 Badonnel, A., et A.N. Garcia Aldrete. 1980. Description de Nadleria mockfordi n. sp., avec

complements sur le genre Nadleria et I'espece Nadleria alpha Badonnel et Garcia Aldrete

(Psocoptera: Lachesillidae). Nouv. Rev. Ent. 10: 229-233. Erwin, T.L. 1983. Tropical forest canopies: the last biotic frontier. Bull. Entomol. Soc. Am. 29:

14-19. Erwin, T.L. 1984. Tambota Reserved Zone, Madre de Dios, Peru: History and description of the

reserve. Rev. per Ent. 27: 1-8. Erwin, T.L. 1989. Canopy arthropod diversity: Chronology of sampling techniques and results.

Rev. per Ent. 32:71-77. Mockford, E.L. 1985. Systematics of the genus Nadleria (Psocoptera: Lachesillidae) with

description of new species and hypotheses on evolution of male external genitalia in the

family Lachesillidae. Ann. Entomol. Soc. Am. 78: 94-100.

Vol. 107, No. 1, January & February, 1996 33

EFFECTIVENESS OF COMBINING FLOTATION

AND STAINING TECHNIQUES WHEN SORTING BENTHIC INVERTEBRATES1

Dianne L. Hall2, Diane L. Wood3, Daryl L. Moorhead2, Robert W. Sites3

ABSTRACT: Several methods for quickly and precisely separating benthic organisms from col- lected substrate have been suggested. We tested the effectiveness of using a flotation technique versus a combination of flotation and staining techniques. The flotation method required less time than combining flotation and staining techniques, but failed to adequately recover annelids. Con- sequently, when knowledge of the contribution to diversity of annelids or other dense inverte- brates is required, use of a combination of flotation and staining techniques is advisable.

An important requirement for studying benthic invertebrates is an accu- rate and efficient method for sorting organisms. Many techniques have been advanced to decrease sorting time while ensuring the retention of captured taxa. Early methods focused on using saturated sucrose solutions as a flotation medium in which benthic invertebrates were separated from substrate by dif- ferences in specific gravity (Anderson 1959, Flannagan 1973, Merickel 1978). Residual sediments were then sorted by hand for invertebrates with high spe- cific gravities. More recent studies have suggested using a combination of techniques, mostly flotation (either sucrose or NaCl) and staining (Thorp and Covich 1991, Wetzel and Likens 1991). In our analysis of the benthic fauna of playa lakes, we found a NaCl solution in conjunction with staining to be a superior technique, especially in the recovery of annelids.

MATERIALS AND METHODS

The benthic fauna of ten playa lakes was surveyed with a 2" ID, single- core sampler. Two hundred fifty substrate samples were taken from each lake and immediately preserved with 10% formalin. In the laboratory, each benthic sample was placed in a wash bucket and immersed in a supersaturated NaCl solution. Floating material was collected with a hand strainer and preserved in 80% ethyl alcohol. The remaining (non-floating) benthic material subse- quently was removed from the NaCl solution and transferred from the wash

1 Received July 24, 1995, Accepted September 28, 1995.

2 Ecology Program -- The Department of Biological Sciences and The Museum, Texas Tech University, Lubbock, Texas 79409-3 131.

3 Wilbur R. Enns Entomology Museum, Department of Entomology, University of Missouri, Columbia, Missouri 6521 1.

ENT. NEWS 107(1): 33-35, January & February, 1996

34 ENTOMOLOGICAL NEWS

bucket into a white enamel sorting pan. Tap water was added to the pan until the sediment was covered by a thin layer of water. Approximately one gm of rose bengal stain was added to the sediment and mixed thoroughly. The mix- ture was allowed to stand for 30 min then returned to the wash bucket where it was thoroughly rinsed with tap water. The washed sediment was then trans- ferred into a clean white enamel pan for sorting by hand.

RESULTS AND DISCUSSION

Retention and removal of collected organisms using the combination of flotation and staining techniques was superior to flotation alone (Table 1). Using the flotation technique alone, one entire family of annelids (Lumbricul- idae) was not detected. Moreover, six times as many leeches (Erpobdellidae) were recovered using the flotation/stain combination technique rather than flotation alone. A G-test of independence (Sokal and Rohlf 1981) revealed significant differences (P = 0.009) in families retrieved using the flotation technique versus the flotation/stain technique. However, when the

Table 1. Number of individuals of each family recovered using the flotation method alone versus a combination flotation/staining technique based on 2500 samples divided equally among 10 playas. Alphabetic superscripts denote those families combined for the G-test. Asterisks denote those families whose presence was probably accidental and not used in the G-test.

Technique Benthic Invertebrate Families Float alone Float/Stain

LumbriculidaeA	0	5
ErpobdellidaeA	7	41
Planorbidae3	6	22
Carabidaec	1	1
CurculionidaeD	7	7
Scarabidaec	3	3
Hydrophilidaec	1	2
ChironomidaeE	8	9
CoenagrionidaeF	4	4
Aculeata*	1	1
Leptoceridae*	1	1
Caenestheriidae°	2	3
CyprididaeG	1	1

Vol. 107, No. 1, January & February, 1996 35

annelids (Lumbriculidae and Erpobdellidae) were removed from the analysis, no significant differences were found between the two techniques (P = 0.333), Therefore, when surveying benthic invertebrates, both flotation and and stain- ing techniques should be used to ensure the detection of all collected organ- isms. However, if annelids are not a concern, the flotation method is more efficient than the combination technique because substrate staining requires approximately an additional 45 min per sample.

ACKNOWLEDGMENTS

We would like to thank the following personnel for assistance in collecting and processing the benthic invertebrates: S. Cox, S. Vaughn, C. Wolf, B. Croyle, S. Davis, M. Secrest, J. Grantham, S. Harrell, J. Holton, and J. Josephson. We also would like to thank T. R. Mollhagen, E.B. Fish, and two anonymous reviewers for editing earlier versions of the manuscript and J.A. Beatty at Southern Illinois University for identifying all non-insect families. This project was funded through a grant to M. Willig, D. Moorhead, T. Mollhagen, E. Fish, and R. Sites from the United States Environmental Protection Agency (#R82 167 1010) entitled "Integrated indicators of stress in playa lakes: wetland ecosystems in a sea of agriculture and aridity." Additional support was provided by The Institute for Environmental Sciences and the Office of Research Services via the aegis of R. Sweazy and F. Bryant. Funding for RWS was provided in part by project #PSSLO232. This is Missouri Agricultural Experiment Station journal series paper No. 12,355.

LITERATURE CITED

Anderson, R.O. 1959. A modified flotation technique for sorting bottom fauna samples. Limnol- ogy and Oceanography 4:223-225.

Flannagan, J.F. 1973. Sorting benthos using flotation media. Technical Report No. 354, Fish- eries Research Board of Canada, Freshwater Institute, Winnipeg, Manitoba, Canada.

Merickel, F.W. 1978. The macrofauna of two West Texas playa lakes with special reference to their use as biological indicators. Unpublished M.S. thesis, Texas Tech Univ. Lubbock, TX.

Sokal, R.R., and FJ. Rohlf. 1981 Biometry. 2nd Edition. W.H. Freeman and Co., New York, NY.

Thorp, J.H., and A.P. Covich. 1991. Ecology and classification of North American freshwater invertebrates. Academic Press, Inc., San Diego, CA.

Wetzel, R.G., and G.E. Likens. 1991. Limnological analysis. 2nd Edition. Springer- Verlag, New York, NY.

36 ENTOMOLOGICAL NEWS

RECORDS OF PROPYLEA QUATUORDECIMPUNCTATA

(COLEOPTERA: COCCINELLIDAE)

FROM LONG ISLAND, NEW YORK: EVIDENCE FOR A

NATURALIZED POPULATION BEFORE 19911

^

Douglas Yanega''

ABSTRACT: Recently published discussions on the distribution and dispersal of the exotic lady beetle Propylea quatuordecimpunctata have suggested that it was not established in either New Jersey or southernmost New York (including Long Island) prior to 1991. Earlier introduction attempts in New Jersey were reportedly unsuccessful, and it has been inferred that the beetle even- tually arrived on Long Island by migrating in from the north in 1991 . I here present collection data and personal observations that suggest that a naturalized population of this species had become established in western Long Island (Queens County) as early as 1989, and propose alternative models of its establishment.

There is a growing literature on the establishment and spread of the exotic aphidophagous coccinellid Propylea quatuordecimpunctata (L.) in northeast- ern North America, with two recent overviews by Wheeler (1990) and Day et al. (1994), which discuss much of the history and prior literature. Introduc- tions were attempted, and presumed to have failed, several times in Delaware, New Jersey, and Oklahoma between 1970 and 1989 (Wheeler 1990, 1993, Day et al. 1994). Accidental introduction in Quebec by waterway has been repeatedly suggested as the origin of the present North American population, and Dysart (1988) suggested further introductions to facilitate its spread. The first U.S. records were in Vermont in 1984 and 1985 (Dysart 1988).

Along with my thesis research in North Floral Park, Queens County, New York, from 1982-1987, I collected vouchers of any insects I had not previ- ously encountered in the area, and I continue to do so, in an attempt to develop a faunistic list of insects in the area (unpublished data). I made no collections in 1988, but in 1989 I collected a specimen of P. quatuordecimpunctata in nearby Nassau Co., and shortly thereafter saw (but did not collect) another specimen in Floral Park (this species is very distinctive in appearance; Gordon 1985). I collected one more specimen the following year in a nearby park, and saw several more individuals in the area. I have seen this species in Queens on an infrequent but regular basis since then. It was not until 1992 that I first recognized its identity, and not until Day et al. (1994) appeared in print that I realized the observations were of possible interest. In a brief visit to the area in 1994, P. quatuordecimpunctata was in fact the only coccinellid I en-

' Received May 25, 1995. Accepted August 12, 1995

2 Illinois Natural History Survey, 607 E. Peabody Dr., Champaign, IL 61820

ENT. NEWS 107(1): 36-38, January & February, 1996

Vol. 107, No. 1, January & February, 1996 37

countered, and in 1995, the only other species seen were Coccinella septem- punctata L. and Harmonia axyridis (Pallas), themselves both imported spe- cies. The specimens collected are deposited in the Snow Museum, University of Kansas (KU), and the Illinois Natural History Survey (INHS), as follows:

Propvlea quatuordecirnpunctata: Additional U.S. collection records: NEW YORK: Nassau Co., Roslyn area, 30-VI-1989, D. Yanega (1 specimen, KU); Queens Co., Alley Park [nr. Queens Vil- lage], 7-VI1I-1990, D. Yanega (1 specimen, KU); Queens Co., Alley Park nr. Queens Village, 28- Vl-1995, D. Yanega (1 specimen, INHS); Suffolk Co., East Hampton, Montauk Point St. Pk., 30-VI-1993, D. Yanega (1 specimen, INHS); Suffolk Co., Southard's Pond nr. Babylon Village, 2-VII-1995, D. Yanega (1 specimen, INHS).

DISCUSSION

My collections and observations suggest that a naturalized population of P. 14-punctata was present on Long Island as early as 1989. There are a few possible explanations for this, none of which corresponds to the present view of this species' establishment in the eastern U.S. In what I would suggest are decreasing degrees of likelihood, these are: (1) an unintentional introduction event directly via the ports of greater New York, independent of the introduc- tions into Quebec and New Jersey, which remained essentially restricted to Long Island until the Quebec-derived population spread into southern New York (2) part of the natural southward spread from Quebec, placing the lead- ing edge of its advancement two years ahead and 200-300 miles farther south than any other confirmed records have indicated (3) a side-effect of an inten- tional introduction event into New Jersey, perhaps the program that began in 1989 (Day et al. 1994), which failed at the site of introduction but sent suc- cessful propagules to nearby Long Island. Any of these alternatives would at least partially invalidate the model proposed by Day et al. (1994; their figure 1). Contacts at the American Museum of Natural History and Cornell Univer- sity in New York report no additional identified specimens from this area over this time period.

ACKNOWLEDGMENTS

I thank Charles G. Helm for his help obtaining background information from NAPIS, and John Bouseman for reviewing the manuscript. The comments of four anonymous reviewers were also helpful and appreciated.

38 ENTOMOLOGICAL NEWS

LITERATURE CITED

Day, W.H., Prokrym, D.R., Ellis, D.R. and Chianese, RJ. 1994. The known distribution of the

predator Propylea quatuordecimpunctata (Coleoptera: Coccinellidae) in the United States,

and thoughts on the origin of this species and five other exotic lady beetles in eastern North

America. Entomol. News 105: 244-256. Dysart, R.J. 1988. The European lady beetle Propylea quatuordecimpunctata: new locality

records for North America. J.N.Y. Entomol. Soc. 96: 119-121. Gordon, R.D. 1985. The coccinellids (Coleoptera) of America north of Mexico. J. N.Y. Entomol.

Soc. 95: 1-912. Wheeler, A.G., Jr. 1990. Propylea quatuordecimpunctata: additional U.S. records of an adven-

tive lady beetle (Coleoptera: Coccinellidae). Entomol. News 101: 164-166. Wheeler, A.G., Jr. 1993. Establishment of Hippodamia variegata and new records of Propylea

quatuordecimpunctata in the eastern United States (Coleoptera: Coccinellidae). Entomol.

News 104: 102-110.

Vol. 107, No. 1, January & February, 1996 39

TWO NEW SPECIES OF DIPLOCENTRUS (SCORPIONES: DIPLOCENTRIDAE) FROM MEXICO1

Debra A. Fritts, W. David Sissom2

ABSTRACT: Two new species of the genus Diplocentrus from Mexico are described, illustrated, and compared to related taxa and others in their respective geographical areas. Diplocentrus ferrugineus occurs in northeastern Mexico in the southern part of Nuevo Le6n, and D. coylei is found in southern Mexico in the northwestern part of Guerrero. Two new records for D. colwelli in Nuevo Le6n are also reported.

The genus Diplocentrus is proving to be one of the most diverse elements of the Mexican and Central American scorpiofauna. Of the thirty species cur- rently recognized as valid, twenty-two have been reported to occur in Mexico. It is evident from ongoing research that many new species remain to be described. This is particularly true for western Mexico, where in certain states no records of the genus exist. Although the diplocentrid fauna of northeastern, central, and southern Mexico (including Yucatan) seems fairly well known, it is clear from closer examination that sampling even in these areas is still largely incomplete. Consequently, it is not possible at this time to provide an accurate estimate of the total number of species in this genus.

It is the purpose here to describe two new forms, one from northeastern Mexico and the other from southern Mexico, based on specimens originating from the American Museum of Natural History (New York), the Louisiana State University Museum of Zoology (Baton Rouge), and the Museum of Comparative Zoology (Harvard University, Cambridge, MA).

Diplocentrus ferrugineus, NEW SPECIES

(Figs. 1-7)

Type Data. - Adult holotype male from 2.7 mi N and 2.4 mi SE La Ascension on La Caballada Rd., Nuevo Leon, Mexico on 19 July 1975 by E. A. Liner; deposited in the Florida State Col- lection of Arthropods, Gainesville.

Etymology. - The specific epithet is based on the Latin word, ferrugineus, for "rust-colored", which refers to the base coloration of this species.

Distribution. - Known only from southern Nuevo Leon, Mexico.

Comparative Diagnosis. - Currently, three other species of Diplocentrus are known from north- eastern Mexico: D. colwelli Sissom, D. diablo Stockwell & Nilsson, and D. whitei (Gervais).

1 Received April 7, 1995. Accepted August 12, 1995.

^ Department of Biology & Geosciences, West Texas A & M University, WTAMU Box 808, Canyon, TX 79016.

ENT. NEWS 107(1): 39-48, January & February, 1996

40 ENTOMOLOGICAL NEWS

Diplocentrus colwelli was described from the mountains in the Monterrey area in central Nuevo Leon (Sissom 1986) and is closely related to the new species. Diplocentrus ferrugineus is larger, with adults exceeding 40 mm in length (the 40-mm female paratype is probably subadult); adults of D. colwelli are less than 40 mm long (the paratype female reported at 44 mm long is almost certainly referable to D. ferrugineus; see "Comments" below). The pedipalp chela palms of male D. ferrugineus are weakly reticulate with the reticulations primarily limited to the dorsal face; in D. colwelli, both the dorsal and external faces of the palms are strongly reticulate. Mor- phometric differences in chela proportions between the two species are also conspicuous: In D. ferrugineus, the male chela is more slender (chela length/depth ratio is 2.19-2.28, compared to i. 78- 1.88) and the chela fingers in both sexes of D. ferrugineus are longer (male fixed finger length/carapace length 0.77-0.88 in D. ferrugineus, 0.62-0.68 in D. colwelli; female ratios 0.65 in D. ferrugineus, 0.56 in D. colwelli).

Diplocentrus diablo is known from the southeastern Rio Grande Valley in Texas and in neighboring Tamaulipas (Ciudad Camargo) in Mexico (Stockwell & Nilsson 1987). The two species are approximately the same size, but D. ferrugineus is light-colored (orange-brown) whereas D. diablo is dark brown. Diplocentrus ferrugineus further differs from it by having lower pectinal tooth counts (9-1 1 in males and 8-9 in females, rather than 12-14 and 9-11, respectively) and a higher modal tarsomere II spine formula (5/5: 6/6: 7/7: 7/7-8, rather than 4/4: 4/5: 5/6: 5/6). The male pedipalps are distinctly more slender in D. ferrugineus, with chela length/depth ratios of 2.19-2.28 (rather than 1.86-2.00); morphometrics of the female chelae in the two species are similar. Finally, the reticulations on the male chelae are very weak in D. ferrugineus, but are pro- nounced in D. diablo.

Of the three species listed above, Diplocentrus whitei is the least similar to D. ferrugineus. Perhaps the only possible confusion in making identifications could be with juveniles of D. whitei. Diplocentrus whitei is a large dark species with adult size to about 70 mm. It has higher pectinal tooth counts (16-20 in males and 14-18 in females) and higher tarsomere II spine counts (6/7: 6/8: 7/8: 7/8); neither character exhibits age-specific variation so they will be useful in separating all age groups of the two species.

Description. - Based on holotype male.

Coloration: Base color of dorsum orange brown with faint dusky pattern; metasomal seg- ment V and telson dark orange brown. Pedipalp chela reddish orange proximally, dark orange brown distally with fingers infuscate. Proximal segments of legs yellow brown, tarsi yellow. Ven- ter light yellow brown. Cheliceral manus yellow brown with faint dusky pattern distally; che- liceral teeth dark reddish brown.

Prosoma: Anterior margin of carapace moderately, coarsely granular (Fig. 1); remainder of carapace smooth to finely granular, lustrous. Sternum with single anteromedian seta and eight additional pairs of setae.

Mesosoma: Tergites finely granular, interspersed with sparse coarse granulation posterolat- erally. Tergite VII weakly bilobed, moderately granulose posterolaterally. Genital operculum moderately setose throughout; pectinal tooth count 11-11. Sternites III-VI smooth, lustrous, mod- erately setose. Sternite VII with submedian carinae vestigial, weak, and smooth; lateral carinae weak, smooth.

Metasoma: Segments I-IV: Dorsolateral carinae on I-III moderate to strong, irregularly gran- ulose; on IV moderate, irregularly granular. Lateral supramedian carinae on I-III strong to mod- erate, irregularly granular; on IV moderate, smooth. Lateral inframedian carinae on I weak.

Vol. 107, No. 1, January & February, 1996 41

irregularly granular; II-III weak, granular; on IV vestigial, weak, smooth. Ventrolateral carinae on MI strong, irregularly crenulate; on HI moderate, irregularly granular; on IV moderate, slightly granular. Ventral submedian carinae on I-II strong, irregularly crenulate; on III weak, granular; on IV vestigial, weak, smooth. Segment V (Fig. 2): Dorsolateral carinae moderate, slightly granular. Lateromedian carinae vestigial, feeble, smooth. Ventrolateral, ventromedian, and ventral trans- verse carinae strong, with distinctly enlarged subconical granules. Ratio of segment II length/width = 1.09; III length/width = 1.31; segment V length/width = 2.57.

Telson (Fig. 2): moderately setose.

Chelicerae; Movable finger distinctly shorter than manus length; fixed finger distinctly shorter than manus width.

Pedipalps: Trichobothrial pattern Type C, orthobothriotaxic (Vachon 1974). Femur (Fig. 3): Dorsal and internal faces moderately granular. Dorsointernal carina strong, granulose; ventro- internal carina vestigial, strong, granulose on anterior half; dorsoexternal carina moderate, irregularly granular; ventroexternal carina vestigial, smooth on posterior half. Ratio of femur length/width = 2.52. Patella (Figs. 4-5): Dorsointernal carina strong, smooth; dorsal median carina faint, smooth; dorsoexternal carina weak, smooth; ventroextemal carina moderate, smooth; ven- trointernal carina strong, smooth. Internal face with basal tubercle bearing three large granules. Dorsal face faintly, smoothly reticulate. Ratio of patella length/width = 2.62. Chela (Figs. 6-7): Dorsal marginal carina strong, irregularly granular; dorsal secondary carina weak, smooth; digi- tal carina strong, smooth; external secondary carina moderate, smooth; ventral external carina ves- tigial, weak at movable finger condyle, smooth; ventromedian carina strong, smooth; dorsointernal carina weak, smooth basally with a few granules by fixed finger; ventrointernal and internal secondary carinae moderate, smooth. Dorsal face of manus feebly, smoothly reticulate. Ratio of chela length/depth = 2.24; of fixed finger length/carapace length = 0.88; movable finger length/chela depth = 1.60.

Legs: Tarsomere II spine formula 5/5 3/3: 6/7 5/6: 7/7 7/7: 7/7 7/7.

Variation. - The other males are about 10% smaller than the holotype in various body dimensions, but otherwise do not differ significantly. The female is similar to the male except in the following characters: (1) the metasomal and pedipalpal segments are proportionately shorter (Table 1); (2) metasomal inframedian carinae are stronger; (3) the carinae of the pedipalp chelae are weak to obsolete, and their dorsal faces bear only faint reticulations; and (4) the pectinal tooth counts are lower (see below). As is typical of Diplocentrus spp., the young specimens are uni- formly pale yellowish in coloration and have rudimentary carination.

Variation in pectinal tooth counts is as follows: in males there were three pectines with 1 1 teeth, two with 10 teeth, and one with nine teeth; in females there were two pectines with nine teeth and two with eight. Morphometric variation is summarized in Table 1, and variation in tar- somere II spine formulas is presented in Table 2.

Measurements. - Holotype male (in mm): Total L, 46.4; carapace L, 5.8; mesosoma L, 14.4; metasoma L, 21.0; telson L, 5.2. Metasomal segments: I LAV, 3.2/3.4; II LAV, 3.6/3.3; III LAV, 3.8/2.9; IV LAV, 4.5/2.7; V LAV, 5.9/2.3. Telson: vesicle LAV/D, 4.2/2.3/2.0; aculeus L, 1.0. Pedipalps: femur LAV, 5.3/2.1; patella LAV, 5.5/2.1; chela LAV/D, 10.1/2.8/4.5; fixed finger L, 5.1 ; movable finger L, 7.2.

42

ENTOMOLOGICAL NEWS

Paratype female (in mm): Total L, 40.0; carapace L, 5.5; mesosoma L, 13.5; metasoma L, 16.6; telson L, 4.4. Metasomal segments: I LAV, 2.5/3.2; II LAV, 2.8/2.8; III LAV, 3.0/2.8; IV LAV, 3.6/2.7; V LAV, 4.7/2.3. Telson: vesicle LAV/D, 3.5/2.5/1.9; aculeus L, 0.9. Pedipalps: femur LAV, 4.0/1.8; patella LAV, 4.1/1.9; chela LAV/D, 8.7/3.1/4.3; fixed finger L, 3.6; movable finger L, 5.2.

Figs. 1-7. Morphology of Diplocentrusferrugineus, new species. All figures are of holotype male. 1, anterior portion of carapace, dorsal aspect; 2, lateral aspect of metasomal segments IV, V, and telson; 3, dorsal aspect of pedipalp femur; 4, dorsal aspect of pedipalp patella; 5, external aspect of pedipalp patella; 6, external aspect of pedipalp chela; 7, dorsal aspect of pedipalp chela..

Vol. 107, No. 1, January & February, 1996 43

Comments. - The paratype female of D. colwelli from Cerro Potosf in south- ern Nuevo Leon is almost certainly referable instead to D.ferrugineus. Unfor- tunately, the specimen could not be located in the California Academy of Sciences (D. Ubick, personal communication), where it was presumably deposited, so it could not be reexamined. In the description of D. colwelli (Sis- som 1986), it was noted that the Cerro Potosf female, at 44 mm, was larger than the other adult female of D. colwelli and that the dorsal margin of its pedi- palp chela was virtually smooth (not granulose). These characters are consis- tent with female characters in D. ferrugineus, based on information available from the single subadult specimen studied herein. Morphometrically, the Cerro Potosf female is closer to D. ferrugineus as well, particularly in the fol- lowing ratios: Chela length/depth = 1.96 (reported as chela length/width in Sissom 1986) and fixed finger length/carapace length = 0.64. Although tar- somere II spine counts overlap in the two species, the specimen's count is very near the modal count for D. ferrugineus, but is at the upper end of the range for D. colwelli. Finally, Cerro Potosf is located in south central Nuevo Leon very near the localities from which D. ferrugineus was taken.

In the course of studying Diplocentrus material from Nuevo Leon, two new records of D. colwelli were found. Two females and a very young speci- men from Cienega de Flores were taken on 14 June 1941 by H. Dybas; these specimens are deposited in the Field Museum of Natural History, Chicago. A male and two females were also taken 3 mi N Galeana on Rayones Road on 23 July 1975 by E. A. Liner, et al.; these specimens are in the Florida State Collection of Arthropods.

Specimens Examined. - MEXICO: Nuevo Leon, 2.7 mi N and 2.4 mi SE La Ascension on La Caballada Rd., 19 July 1975 (E. A. Liner), 1 holotype male, 1 paratype male, 1 adult? female, 2 juv. females (FSCA); 3 mi N General Ignacio Zaragoza, 19 July 1974 (E. A. Liner, et al.), 1 male (FSCA); 1-3.3 mi N General Ignacio Zaragoza, 20 July 1975 (E. A. Liner), 3 juvs. in three vials (FSCA); 0.6 mi S Poterio Prieto in Arroyo Mesquital, 16 July 1974 (E. A. Liner, et al.), 1 male (partial specimen) (FSCA); 12.6 mi W, 1.4 mi N Dr. Arroyo on El Pequeno Road, 21 July 1975 (E. A. Liner), 1 juv. (FSCA).

Diplocentrus coylei, NEW SPECIES

(Figs. 8-14)

Type Data. - Adult male holotype from outside Grutas de Cacahuamilpa, Guerrero, Mex- ico on 8 June 1982 by F. Coyle; deposited in the Museum of Comparative Zoology, Harvard Uni- versity, Cambridge, Massachusetts.

Etymology. - The specific epithet is a dedication to Dr. Frederick Coyle, who collected the holotype, for his contributions to arachnology.

Distribution. - Known only from northern Guerrero, Mexico.

44 ENTOMOLOGICAL NEWS

Comparative Diagnosis. - Two species of the genus Diplocentrus have been reported from Guerrero: D. tehuacanus Hoffmann and D. magnus Beutelspacher & Lopez-Forment. Diplocen- trus coylei appears most similar to D. tehuacanus, but differs in a number of important characters. The anterior margin of the carapace is very finely granular in D. coylei, but is granulose in D. tehuacanus. In D. coylei, the metasomal carinae are stronger, with the dorsolaterals and lateral supramedians distinctly granular. Metasomal segment III bears ten carinae in D. coylei (the lateral inframedians are present), but only eight carinae in D. tehuacanus. The dorsolateral, lateral supra- median, and ventrolateral carinae of metasomal segment IV are all moderate to strong in D. coylei, but are obsolete or vestigial, weak, and smooth in D. tehuacanus. Males of D. coylei have the dor- sal and external surfaces of the pedipalp chelae reticulate, but only the dorsal face bears reticula- tions in D. tehuacanus.

There are also distinctive morphometric differences in the pedipalps and metasoma between the two species, particularly in males. Some ratios demonstrating these differences are as fol- lows (female ratios given in parentheses): pedipalp chela length/depth = 2.81-3.15 (2.10) in D. coylei, but is 2.54 (1.92) in D. tehuacanus; pedipalp patella length/width = 2.83-3.20 (2.48) in D. coylei, but is 2.77 (2.07) in D. tehuacanus.

Diplocentrus magnus is a much larger, dark-colored species with adults approximately 100 mm in length. In addition, the tarsomere II spine formula of the legs (4/6-7: 4-5/7: 5-6/7: 5-6/7-8) is quite different from that in D. coylei. Adult males of D. magnus are currently unknown, so mor- phometric comparisons with males of D. coylei cannot be made.

Description. - Based on holotype male.

Coloration: Base color uniformly orange to orange brown with a fairly strong underlying dusky pattern on carapace and anterior half of each tergite. Carinae of metasoma and pedipalps dark reddish brown. Distal part of pedipalp chela palm and fingers slightly darker orange brown. Proximal segments of legs yellow brown, distal segments yellowish. Venter light yellow brown. Cheliceral manus yellow brown with faint dusky pattern distally; cheliceral teeth dark reddish brown.

Prosoma: Anterior margin of carapace densely, finely granular (Fig. 8); remainder of cara- pace smooth to finely granular, lustrous. Sternum with single anteromedian seta and nine addi- tional pairs of setae.

Mesosoma: Tergites finely granular, interspersed with sparse coarse granulation posterolat- erally. Tergite VII weakly bilobed, granuloreticulate posterolaterally. Genital operculum with four pairs of larger setae along posterior margin and one median pair; microsetae present along pos- teromedial margins and on genital papillae. Pectinal tooth count 16-15. Sternites III-VI minutely punctate, lustrous, sparsely setose. Sternite VII with submedian and lateral carinae vestigial, weak, and finely granular.

Metasoma: Segments I-IV: Dorsolateral carinae on l-III moderate, irregularly granular; on IV moderate, smooth to granular. Lateral supramedian carinae on I-IV moderate to strong, irreg- ularly granulose. Lateral inframedian carinae on I moderate, irregularly granulose; on II-III mod- erate, irregularly granular; on IV weak, almost smooth. Ventrolateral carinae on I-II strong, crenulate; on III moderate, crenulate; on IV moderate, irregularly crenulate. Ventral submedian carinae on I-II moderate, irregularly granulose; on III-IV vestigial, weak, granular. Dorsal and lat- eral intercarinal spaces of I-II granuloreticulate, of III-IV granular. Segment V (Fig. 9): Dorsolat- eral carinae moderate, smooth. Lateromedian carinae vestigial, weak, smooth. Ventrolateral, ventromedian, and ventral transverse carinae strong, with distinctly enlarged subconical granules. Ratio of segment II length/width = 1.17; III length/width = 1.30; segment V length/width = 2.79.

Vol. 107, No. 1, January & February, 1996 45

Telson (Fig. 9): moderately setose.

Chelicerae: Movable finger distinctly shorter than manus length; fixed finger distinctly shorter than manus width.

Pedipalps: Trichobothrial pattern Type C, orthobothriotaxic (Vachon 1974). Femur (Fig. 10): Dorsal and internal faces moderately, coarsely granular; dorsal face flattened throughout. Dorsointernal carina strong, granulose; ventrointernal carina strong, granulose; dorsoexternal carina moderate, irregularly granular; ventroexternal carina obsolete. Ratio of femur length/width = 2.78. Patella (Figs. 1 1-12): Dorsointernal carina strong, smooth; dorsal median carina vestigial, smooth; dorsoexternal carina weak, smooth; ventroexternal carina moderate, smooth; ventrointer- nal carina strong, moderately granulose. Internal face with basal tubercle bearing four large gran- ules; distal portion densely, finely granular. Dorsal face weakly, smoothly reticulate. Ratio of patella length/width = 3.20. Chela (Figs. 13-14): Dorsal marginal carina strong, granulose; dorsal secondary carina weak, smooth; digital carina strong, smooth; external secondary carina weak, smooth; ventroexternal carina vestigial, weak at movable finger condyle, smooth; ventromedian carina very strong, smooth; dorsointernal carina vestigial, granular; ventrointernal and internal secondary carinae weak, smooth. Dorsal and external faces of manus moderately, smoothly retic- ulate throughout. Ratio of chela length/width = 4.83; chela length/depth = 3.15; of fixed finger length/carapace length = 0.85; of movable finger length (normal left side)/chela depth = 1.70.

Legs: Tarsomere II spine formula 4/4 4/5: 5/5 5/5: 5/6 5/6: 6/6 4/5 (count of left leg IV abnormal).

Variation. - The female is similar to the male except in the following characters: (1) the metasomal segments and pedipalpal femur and patella are proportionately shorter, and the chela more robust (Table 1); (2) the dorsal and lateral carinae of the metasomal segments are weaker; (3) the carinae of the pedipalp chelae are weaker, and the reticulations of the dorsal and external faces are faint; and (4) pectinal tooth counts are lower (see below). As is typical of Diplocentrus spp., the young specimens are pale yellow to yellow brown in coloration, but have a distinct dusky pattern on the carapace, tergites, pedipalps, and metasoma; they also have rudimentary carination.

Variation in pectinal tooth counts is as follows: in males there were two pectines with 16 teeth, two with 15 teeth, and two with 14 teeth; in females there were three pectines with 13 teeth, four with 12 teeth, and one with 1 1 teeth. Morphometric variation is summarized in Table 1, and variation in tarsomere II spine formulas is presented in Table 2.

Measurements. - Holotype male (in mm): Total L, 53.2; carapace L, 6.8; mesosoma L, 17.1; metasoma L, 23.9; telson L, 5.4. Metasomal segments: I LAV, 3.7/3.9; II LAV, 4.1/3/5; III L/W, 4.3/3.3; IV LAV, 5.1/2.9; V LAV, 6.7/2.4. Telson: vesicle LAV/D, 4.4/2.4/1.9; aculeus L, 1.0. Pedipalps: femur LAV, 7.5/2.7; patella LAV, 8.0/2.5; chela LAV/D, 14.5/3.0/4.6; fixed finger L, 5.8; movable finger L, 8.5. Note: The movable finger of the right side is disproportionately longer than on the left side; the measurement for the left movable finger length is 7.8 mm.

Paratype female, Las Granadas (in mm): Total L, 56.5; carapace L, 7.6; mesosoma L, 20.7; metasoma L, 22.5; telson L, 5.7. Metasomal segments: I LAV, 3.4/4.3; II LAV, 3.8/3.9; III LAV, 4.2/3.7; IV LAV, 4.9/3.5; V LAV, 6.2/2.9. Telson: vesicle LAV/D, 4.6/3.0/2.5; aculeus L, 1 . 1 . Pedi- palps: femur LAV, 6.1/2.7; patella LAV, 6.7/2.7; chela LAV/D, 13.0/4.6/6.2; fixed finger L, 5.4; movable finger L, 7.7.

Specimens Examined. - MEXICO: Guerrero, Gruta de Cacahuamilpa (W 99.30, N 18.40), 2 Sept 1966 (J. & W. Ivie), 1 juv. (AMNH); outside Gruta de Cacahuamilpa, 8 June 1982 (F. Coyle), 1 holotype male (MCZ); summit, 4 mi W Cacahuamilpa (W 99.34, N 18.41), 3 Sept 1966 (J. & W. Ivie), 1 male, 1 female, 1 juv. (AMNH); Las Granadas, 12 July 1980 (E. Martin & R. Garcia), 1 male, 1 female (AMNH-OFF).

46

ENTOMOLOGICAL NEWS

Figs. 8-14. Morphology of Diplocentrus coylei, new species. All figures are of holotype male. 8, anterior portion of carapace, dorsal aspect; 9, lateral aspect of metasomal segments IV, V, and tel- son; 10, dorsal aspect of pedipalp femur; 1 1 , dorsal aspect of pedipalp patella; 12, external aspect of pedipalp patella; 13, external aspect of pedipalp chela; 14, dorsal aspect of pedipalp chela.

Vol. 107, No. 1, January & February, 1996 47

Table 1 . Ranges in morphometric characters (ratios) of Diplocentrus ferrugineus, new species and D. coylei, new species. Included herein are additional ratios (not mentioned in the text) that may prove to be of value in separating these species from others in the genus. Only a single female was available for D. ferrugineus. Abbreviations are as follows: L = length, W = width, D = depth.

Ratio D. ferrugineus D. coylei

3 Males ( 1 Female) 3 Males (2 Females)

Chela LAV	3.36-3.61 (2.81)	4.17-4.83(2.83-3.10)
Chela L/D	2.19-2.28(2.02)	2.81-3.15(2.09-2.10)
Fixed Finger L/carapace L	0.77-0.88 (0.65)	0.79-0.86(0.70-0.71)
Movable Finger L/metasoma V L	1.09-1.22(1.11)	1.16-1.21 (1.24-1.26)
Metasoma III LAV	1.21-1.31 (1.07)	1.28-1.32(1.14-1.18)
Metasoma V LAV	2.30-2.57 (2.04)	2.55-2.79(2.14-2.23)
Pedipalp Femur LAV	2.35-2.52 (2.22)	2.61-2.78 (2.22-2.26)
Movable Finger L/Chela D	1.35-1.60(1.21)	1.50-1.70(1.24-1.26)

Table 2. Variation in tarsomere II spine formulas in Diplocentrus ferrugineus and D. coylei, new species. A few specimens were missing legs.

D. ferrugineus

Leg	Spine row 3	4 5	6	7	8
I	Prolateral 1	11	1
	Retrolateral 1	8	4	-	-
II	Prolateral	3	10	-	-
	Retrolateral	-	10	3	-
III	Prolateral	1	1	8	1
	Retrolateral	1	-	7	3
IV	Prolateral	-	1	10	3
	Retrolateral	-	-	7	7

D. coylei
Leg	Spine row 1	234	5	6
I	Prolateral 1	8	3
	Retrolateral	1 1	11	-
II	Prolateral	1	12	-
	Retrolateral	.	12	-
III	Prolateral	.	2	12
	Retrolateral	.	-	14
IV	Prolateral	1	-	12
	Retrolateral	.	1	12

48 ENTOMOLOGICAL NEWS

ACKNOWLEDGMENTS

We are grateful to Douglas Rossman of the Museum of Zoology, Louisiana State Univer- sity, for providing the specimens of D. ferrugine us for study; these specimens are now deposited in the Florida State Collection of Arthropods (FSCA), Gainesville, Florida. We also thank Her- bert W. Levi of the Museum of Comparative Zoology (MCZ) and Norman I. Platnick of the Amer- ican Museum of Natural History, New York (AMNH) for providing the specimens of D. coylei. Frederick Coyle of Western Carolina University, Cullowhee, NC allowed us access to the collec- tion data from his field notes. We are extremely grateful for the diligent reviews of the manuscript provided by Richard M. Haradon of Andover, Massachusetts and Victor Fet of Loyola University, New Orleans. We are also grateful to Darrell Ubick of the California Academy of Sciences for information on the paratype of D. colwelli. Page charges were paid by the Department of Biology & Geosciences, West Texas A & M University.

LITERATURE CITED

Beutelspacher, C. R. and W. Lopez-Ferment. 1991. Una especie nueva de Diplocentrus (Scor-

pionida: Diplocentridae) de Mexico. An. Inst. Biol., Univ. Nac. Auton. Mexico, Ser. Zool.

62(1): 33-40. Francke, O. F. 1977. Scorpions of the genus Diplocentrus from Oaxaca, Mexico (Scorpionida,

Diplocentridae). J. Arachnol., 4: 145-200. Sissom, W. D. 1986. Diplocentrus colwelli, a new species of scorpion from northern Mexico

(Diplocentridae). Insecta Mundi 1: 255-258. Stockwell, S. A. and J. A. Nilsson. 1987. A new species of Diplocentrus Peters from Texas

(Scorpiones, Diplocentridae). J. Arachnol., 15: 151-156. Vachon, M. 1974. Etude des caracteres utilises pour classer les families et les genres de

Scorpions (Arachnides). Bull. Mus. natn. d'Hist. Nat. (Paris), ser. 3, 104:857-958.

Vol. 107, No. I, January & February, 1996 49

FIRST TEXAS RECORDS OF FIVE GENERA

OF AQUATIC BEETLES

(COLEOPTERA: NOTERIDAE, DYTISCIDAE, HYDROPHILIDAE) WITH HABITAT NOTES1

Sharon Knight Jasper2, Roy C. Vogtsberger*

ABSTRACT: Five genera of aquatic beetles are reported from Texas for the first time. Species recorded include Suphis inflatus (Noteridae), Hoperius planatus (Dytiscidae), Dibolocelus ovatus, Hydrobiomorpha casta, and Sperchopsis tessellata (Hydrophilidae). Habitat notes are reported for four of these. In addition, some locality and habitat data are provided for Helobata larvalis (Hydrophilidae) which has only recently been recorded from Texas as Helobata striata. Label data are listed for 168 specimens representing the six genera in Texas.

This paper is a fortuitous result of surveys made from 1991 to 1995 on the Haliplidae of Texas by the senior author, and on potential predators of Culici- dae larvae in the upper Gulf Coast region of Texas by the junior author. Five genera of aquatic Coleoptera previously unreported from Texas were encoun- tered in our samples. Additional information was obtained from material in the Insect Collection of the Department of Entomology at Texas A&M University (TAMU). Recorded localities and ranges for each species and available habi- tat notes are presented. Each of these genera is either monotypic or is repre- sented in the United States by a single species. Unless otherwise indicated, the collection data represent single specimens and the identifications were made or confirmed by the authors. Specimens collected by the authors are indicated by their initials in the locality data. The sexes of the beetles are given when known. Habitats from which more than one of these species were collected are described under the first species listed, and referred to briefly in subsequent species discussions. Many of the collections were made at the Runnell's Fam- ily Mad Island Preserve, southwest of Houston, and the Roy E. Larsen Sandy- land Sanctuary, north of Beaumont (both of which are properties of The Nature Conservancy of Texas), the Anahuac National Wildlife Refuge, just east of Houston, and the J.D. Murphree Wildlife Management Area, south of Port Arthur. Representative specimens from this study are deposited in the Insect Collection of the Department of Entomology at Texas A&M University.

1 Received July 24, 1995. Accepted September 9, 1995.

2 Department of Biology, Texas A&M University, College Station, TX 77843-3258.

3 Department of Entomology, Texas A&M University, College Station, TX 77843-2475.

ENT. NEWS 107(1): 49-60, January & February, 1996

50 ENTOMOLOGICAL NEWS

NOTERIDAE Genus Suphis Aube 1 836 Suphis inflatus (LeConte)

Colpius inflatus LeConte 1863: 22

Copius inflatus; Arnett 1973: 205

Coepius inflatus; Arnett 1983: 9-1

Suphis inflatus; Spongier and Folkerts 1973: 501

Suphis inflatus (LeConte) was originally described in the genus Colpius. Spangler and Folkerts (1973) transferred this species to Suphis and described its third instar larva. This is the only known representative of the genus in the United States. This beetle has been listed from Florida and Louisiana (Crotch and Cantab 1873, Young 1954 [in Colpius], Spangler and Folkerts 1973, Arnett 1973 [in Copius], 1983 [in Coepius]). Later it was recorded from Alabama, Georgia and South Carolina (Spangler and Folkerts 1973, Folkerts and Donovan 1974). Brigham et al. (1982) found this species in both North and South Carolina. A New York locality followed by a question mark was listed by Crotch and Cantab (1873), but this record is very doubtful as Suphis inflatus has not been reported from the Northeast by any other author. The records here extend the known range of this species westward from Louisiana to Brazos and Matagorda Counties of southeastern Texas (Map 1 ).

The habitat of S. inflatus is characterized as "sinkhole ponds, lakes and marshes" and it "...apparently prefers relatively permanent bodies of water, often of low pH" (Young 1954). The habitats at the following localities are consistent with those previously recorded. Alligator Lake, located in the Roy E. Larsen Sandyland Sanctuary of southeastern Texas, had a pH of 4.5 and is a large, shallow, catchment lake mostly covered with Nymphaea sp. Shovel- er's Pond, located in the Anahuac National Wildlife Refuge just east of Hous- ton, is a large, permanent pond with several types of submergent and emergent vegetation and Lemna sp. None of the specimens of S. inflatus collected in our study were taken at lights except those in underwater light traps. This suggests that this species rarely leaves the water or has diurnal flight activity. Fifty-two specimens were taken in seven counties.

TEXAS RECORDS. Brazos Co.: Postoak Lake, TAMU, 18 Jul 1972, J. Roberts. Chambers Co.: Large shallow pool just E of Trinity River @ IH 10, 9 Aug 1991, SKJ. Anahuac National Wildlife Refuge, Shoveler's Pond, 7 Jun 1993, RCV. Hardin Co.: Roy E. Larsen Sandyland Sanctuary, Alligator Lake, 18 Aug 1992, 2 adults; 17 May 1993, 6 adults; 3 Sep 1994, 4 adults; underwater light trap, 4 Sep 1994, 2 adults, SKJ. Roy E. Larsen Sandyland Sanctuary, temporary pool, 18 Aug 1992, 2 adults; 17 May 1993, SKJ. Jefferson Co.: Hwy 365W, 2.3 km W of 823N,

Vol. 107, No. 1, January & February, 1996 51

marsh, 1 1 Aug 1991, SKJ. Matagorda Co.: Mad Island Slough N of lake, underwater light trap, 19 Jun 1993, SKJ. San Jacinto Co.: pond on Loop 424, 0.48 km N of Shepherd, 6 Sep 1992, SKJ. Tyler Co.: marsh of Steinhagen Lake, @ Hwy 90 just W of Martin Dies Cherokee Unit, 21 M 1991, 3 adults; 31 Aug 1991, SKJ. Temple-Inland Forest Lake Club @ swamp, 27 Mar 1993, 6 adults, SKJ; 10 Jun 1995, 19 adults, J.R. Gibson.

DYTISCIDAE

Genus Hoperius Fall 1927

Hoperius planatm Fall

Hoperius planatm Fall 1927: 177

The monotypic genus, Hoperius, was described from a single male spec- imen taken at lights in Hempstead County, Arkansas (Fall 1927). In addition to Lawrence County, Arkansas, Spangler (1973a) reported it from Talbot County, Maryland, Florence and Horry Counties, South Carolina [from Kirk 1970], and Nansemond County, Virginia. A single specimen taken at lights in Elmore County, Alabama, was reported by Folkerts and Donovan (1974), extending the range of this species southward in the United States. Michael and Matta (1977) summarized the known distribution of Hoperius planatus as "south from Maryland to South Carolina and west to Alabama and Arkansas." Anders Nilsson (pers. comm., 1994) confirms that the species has not previ- ously been reported from Texas. Our collection data indicate a southwestern range extension from Arkansas to Montgomery County in southeastern Texas (Map 1).

Michael and Matta (1977) stated "This is strictly a woodland pool spe- cies." Spangler (1973a) reported collecting both adults and immatures of H. planatus on several occasions in Talbot County, Maryland, in woodland ponds which lacked living vegetation but contained rotting leaves. In the same paper, he described the third instar larva and the pupa. The three specimens from Hardin County, in southeastern Texas, were collected by dip net from a swamp with a depth of less than 20 cm. The only macrophytes in the swamp were the black gum trees and the bottom was covered with decaying leaves over a firm sand substrate. The water had a pH of 4.5 and a very low dissolved oxygen level of 1 .2 ppm. All specimens of H. planatus from Montgomery County were taken at lights (Wappes, pers. comm., 1995). Intensive collecting efforts with dipnets, underwater light traps, bottle traps, and both mercury vapor and ultraviolet lights at the Roy E. Larsen Sandyland Sanctuary failed to produce more specimens. This beetle indeed deserves its common name, "the rare predacious diving beetle." Eight specimens have been collected from two Texas counties.

52 ENTOMOLOGICAL NEWS

TEXAS RECORDS. Hardin Co.: Roy E. Larsen Sandyland Sanctuary, swamp of Nyssa sylvat- ica, 19 Aug 1992, female; 18 May 1993, 2 males, SKJ. Montgomery Co.: The Woodlands, 5-7 Apr 1978, female; 20-23 Apr 1978, one male, one female; 12 May 1978; 2 May 1980, male, J.E. Wappes.

HYDROPHILIDAE

Genus Dibolocelus Bedel 1891

Dibolocelus ovatus (Gemminger and Harold)

Hydrophilus ovalis Ziegler 1844: 45 (nee Laporte 1840) Hydrophilus ovatus Gemminger and Harold 1868: 476 (nom. nov.) Dibolocelus ovatus; Young 1954: 196

The genus Dibolocelus is represented in the United States by a single species, D. ovatus (Gemminger and Harold). Dibolocelus superficially resem- bles Hydrophilus in general size and habitus, but differs in having the proster- num completely divided into two lobes, pubescence on the abdominal sternites, a characteristic body shape, and sexually dimorphic maxillary palpi. Hansen (1991) reduced Dibolocelus to a subgenus of Hydrophilus based on his claim that these characters are autapomorphies. After having studied his argument and obtained the opinions of other coleopterists specializing in the Hydrophiloidea (M. Archangelsky, A. Smetana, S. Testa, pers. comms., 1995), we have decided to accept the generic status of Dibolocelus in this paper based on several morphological characters in both the larval and adult stages. Dibolocelus has a strictly New World distribution while Hydrophilus (s.s.) is found worldwide.

Young (1954) reported D. ovatus as ranging from New York, west to Michigan and Indiana, and south to Florida. Wooldridge (1967) added Illinois to the range. This distribution in the eastern United States was extended north- ward into Canada with records from Ontario and Quebec (Bousquet 1991). In the southern United States, Testa and Lago (1994) extended the range of D. ovatus westward to Mississippi. Two adult specimens, used for producing off- spring in studies of the preimaginal stages of the species, were reported by Archangelsky and Durand (1992) from a seemingly disjunct population in Latimer County, Oklahoma. The only documented previous collections of D. ovatus in Texas were recorded by Foster (1972) in his unpublished thesis. The two specimens he recorded were taken on 4 May 1959 and 5 May 1962 from unknown locations in Nacogdoches Co. in eastern Texas. The specimens were not examined, but because the identifications were made by D.P. Wooldridge, an authority on the Hydrophiloidea, they are considered reliable. Our records extend the known distribution of this species westward into Texas to Hidalgo and Cameron Counties (Map 1 ).

Vol. 107, No. 1, January & February, 1996 53

Several authors have documented the preference of D. ovatus for large, deep, well-vegetated bodies of standing water (Young 1954, Smetana 1988). This beetle has also displayed a propensity for being attracted to lights. Kirk (1970) reported D. ovatus being taken at lights in July at Myrtle Beach, South Carolina, and all of our specimens for which data are available were collected at lights. Testa and Lago (1994) concluded that specimens of D. ovatus are "not encountered frequently." This is a large beetle (27-32 mm) and our col- lections from Texas confirm that it is rarely taken as compared to other large aquatic beetles. Archangelsky and Durand (1992) added considerably to the knowledge about this genus and species by observing its bionomics and describing the preimaginal stages from specimens reared in the laboratory. Twenty-one specimens from eleven counties are recorded here.

TEXAS RECORDS. Bee Co.: Beeville, 7 Sep 1938, male, C.G. Johnson. Brazos Co.: College Station, 16 Apr 1951, female, H.J. Reinhard; 17 Apr 1977, male, R.S. Peigler; lOOct 1977, male, J.J. Smith. Cameron Co.: Brownsville, 23 Jun 1938, female; 15 Aug 1938, female, D.C. Earley. Chambers Co.: Anahuac, Mosquito Control District Building, at mercury vapor lights, 22 Apr 1994, male; 27 Jun 1994, male; 2 Oct 1994, female, RCV. Hidalgo Co.: Tex. Exp. Sta., light trap, 16 Jun 193?, female, J.C. Gaines. Jefferson Co.: J.D. Murphree Wildlife Management Area Main Office on SH 73, mercury vapor light, 28 Apr 1995, one male, one female, RCV. Matagorda Co.: 16 km N Palacios, 1 1 Mar 1991, male, Kenny Sexton. Mad Island Preserve, at light, 18 Jun 1993, SKJ & W.B. Godwin. Montgomery Co.: The Woodlands, 28-29 Apr 1978, one male, one female; 7 Apr 1980, female, J.E. Wappes. Nacogdoches Co.: 4 May 1959; 5 May 1962, del. D.P. Wooldridge. San Patrick) Co.: Welder Wildlife Ref., 27 Jun 1969, female. Board & Hafernik. Wood Co.: Mineola Civic Center, at lights, 19 Mar 1987, male, W.B. Godwin.

Genus Hydrobiomorpha Blackburn 1889 Hydrobiomorpha casta (Say)

Hydrophilus castus Say 1835: 170 Hydrocharis obtusatus (Say); LeConte 1855: 369 Hydrous tenebrioides Jacquelin DuVal 1856: 50 Hydrocharis perfectus Sharp 1882: 61 Hydrocharis castus; Horn 1876: 251

Hvdrophilus (Neohydrophilus) castus; d'Orchymont 191 1: 62 Neohydrophilus castus; Knisch 1924: 234 Hydrobiomorpha casta; Mouchamps 1959: 328

Hydrobiomorpha casta (Say) was reported by Young (1954) as Neo- hydrophilus castus in the southern United States from Florida to Louisiana. Spangler (1973b) expanded this distribution to the south to include Cuba,

54 ENTOMOLOGICAL NEWS

Mexico, Guatemala, and Panama. Brigham et al. (1982) added both North and South Carolina to the known range, extending the distribution northward in the United States. Our records indicate a spread in distribution to Chambers and Hardin Counties in southeastern Texas which represent the westernmost range in the United States presently known for this hydrophilid (Map 1 ).

Young (1954) characterized the habitat of//, casta as "...cypress ponds, roadside ditches, sinkhole ponds, and swamps principally in the flatwoods" and further stated that this beetle was found "infrequently." Testa and Lago (1994) collected specimens only at lights, mostly near a small eutrophic wood- land lake and a large, well-established lily pond. The majority of our speci- mens from Chambers County, Texas, were collected in a large marsh when the salinity ranged from 2 to 4 ppt. Specimens from Jefferson County, Texas, were collected in a marsh during a period when the salinity ranged from 2 to 9 ppt. Both marshes had experienced higher salinity levels than the ranges shown here, but none of these beetles were taken during those periods. The vegeta- tion at both marshes is predominately Spartina patens (Ait.) Muhl. Ecological notes on Alligator Lake, in southeastern Texas, are included in the discussion of Suphis inflatus. Grass Pond, located in the Roy E. Larsen Sandyland Sanc- tuary in southeastern Texas, is a large, shallow pond which dries completely during some years. At its maximum extension, the outer portion is swamp with tree cover (Finns taeda L. and Nyssa sylvatica Marsh.) and the firm sand bot- tom is completely covered with sphagnum moss. This grades into an area of grass which extends for about 30 meters. The large central area has more sphagnum and about 10% cover by Nymphaea sp. The pH was 5.6 in August, 1992. More than half of all specimens collected in this study were taken with submerged bottle traps like those described by Hilsenhoff (1987), and perhaps the success in collecting this species was due to use of these traps. The third instar larva of//, casta was described by Spangler (1973b) from a specimen collected in Bibb County, Alabama. Texas records include 40 specimens col- lected from three counties.

TEXAS RECORDS. Chambers Co.: Double Bayou, at light, 6 Jun 1975, J.S. Ashe & M.L. Hoi- comb. Anahuac National Wildlife Refuge, 4.9 km SE of Visitor Info Booth, marsh, 12 Jul 1993; 13 Jul 1993, 2 adults; 5 Mar 1994, 2 adults; 19 Mar 1994, 2 adults; 9 Apr 1994, 3 adults; 23 Apr 1994, 2 adults; 7 May 1994; 25 May 1994; 16 Jun 1994, 3 adults; 28 Jun 1994, 4 adults; 12 Jul 1994, 2 adults; 26 Jul 1994; 23 Aug 1994, 1 larva and 2 adults; 30 May 1995, RCV. Hardin Co.: Roy E. Larsen Sandyland Sanctuary, Grass Pond, 18 May 1993, SKJ; Roy E. Larsen Sandyland Sanctuary, mercury vapor light by Alligator Lake, 3 Sep 1994, 5 adults, SKJ. Alligator Lake, 3 Sep 1994, SKJ. Jefferson Co.: J.D. Murphree Wildlife Management Area, 11 km S of Port Arthur, 0.16 km E of Lost Lake, brackish marsh, 6 Mar 1994; 23 Aug 1994, RCV. J.D. Murphree Wildlife Management Area Main Office on SH 73, mercury vapor light, 28 Apr 1995, 2 adults, RCV.

Vol. 107, No. 1, January & February, 1996 55

Genus Sperchopsis LeConte 1 862

Sperchopsis tessellata (Ziegler)

Spercheus tessellatus Ziegler 1844: 44 Sperchopsis tesselatus; LeConte 1862: 47 Hydrobius tesselatus; Horn 1873: 133 Hydrobius tessellatus; Horn 1890: 266 Spercheus tesselatus; Schwarz and Barber 1918: 135 Hydrocyclus tesselatus; Knisch 1921: 102 Hydrocyclus tessellatus; Winters 1926: 53 Sperchopsis tessellatus; d'Orchymont 1928: 93 Sperchopsis tessellata; Smetana 1988: 72

Sperchopsis is a monotypic genus originally described by LeConte (1862). Spangler (1961) provided an excellent review of the nomenclature, biology, and distribution of Sperchopsis tessellata (Ziegler), and described its larvae and pupa. This species has been recorded from numerous states and provinces in eastern North America, ranging from Nova Scotia and Ontario, Canada, south to Florida and Arkansas (Young 1954, Spangler 1961, Kirk 1969, 1970, Arnett 1973, 1983, Brigham et al. 1982, Warren 1985, White et al. 1985, Smetana 1988, Bousquet 1991, Testa and Lago 1994). Our records extend the known range of S. tessellata into East Texas, with Brazos County representing the westernmost point of known distribution in the United States (Map 1).

The typical habitat of Sperchopsis was characterized by Young (1954) as "...fairly swift, sand-bottomed streams, where it occurs in leaf drift in eddies and backwaters or clinging to logs and debris" and by Spangler (1961) as "margins of cold, clear, rapidly flowing streams," and especially "undercut gravelly and sandy stream banks with overhanging roots..." This type of lotic habitat is unusual for most hydrophilid beetles, and undersampling of this habitat is probably one of the reasons for its scarcity in most collections. Although Warren (1985) routinely sampled typical Sperchopsis habitat at 175 sites in Kentucky, he found only one adult and one larva in two streams which had sandy to gravelly undercut banks with overhanging roots or vegetation.

Kirk (1969, 1970) recorded S. tessellata in South Carolina from tangle- foot screens located between cotton fields, or between cotton fields and wood- lands, and also from beach drift on the shores of lakes, bays or oceans. These habitats depart from the "typical" reported habitat for Sperchopsis and proba- bly indicate dispersing individuals. The habitats recorded here (coarse panic- ulate organic matter [CPOM], submerged dead limb, and drift in streams) agree with what is considered "typical" habitat for this species. Likewise, the

56 ENTOMOLOGICAL NEWS

Winter's Bayou specimens, from San Jacinto County in southeastern Texas, were collected from dead branches in a sandy-bottomed stream. A total of twenty-nine specimens are reported from five counties in Texas.

TEXAS RECORDS. Anderson Co.: Boxes Creek (in drift), on submerged dead limb, 6 Nov 1960, 11 adults, H.R. Burke. 16 km SW of Elkhart, 15 Mar 1961, 2 adults, H.R. Burke. Brazos Co.: Bryan, Sep 1990, 2 adults, C. Moomaw. San Augustine Co.: Turkey Creek @ FM103, CPOM in gravel stream, 10 May 1994, 2 adults, SKJ. San Jacinto Co.: Sam Houston National Forest, Double Lake, 9 Apr 1977, Reed, Peigler, Plitt. Sam Houston National Forest, Big Creek @ Big Creek Scenic Area, 26 Sep 1992, SKJ; 1 1 Jun 1995, J.R. Gibson. Sam Houston National Forest, Winter's Bayou @ Lone Star Trail, N of FM 1725, 4 Dec 1993, 4 adults; 4 Jan 1994, 2 adults; 16 Sep 1994; 14 Oct 1994, J.R. Gibson. Tyler Co.: US190 @ Big Cypress Creek, 2.7 km W of FM256N, 7 Mar 1992, larva, SKJ.

Genus Helobata Bergroth 1888 Helobata larvalis (Horn)

Hydrophilus striatus Brulle 1841: 58 Helopellis larvalis Horn 1873: 137

Helobata striata; Young 1954: 185, Richmond 1962: 88, Spangler and Cross 1972: 413, Arnett 1973: 223, Brigham et al. 1982: 10.79, Arnett 1983: 12-11, Fernandez and Bachmann 1987: 154, Testa and Lago 1994: 50

Helobata larval is; Hansen 1991: 293

Helobata larvalis (Horn), the only species representing the genus Helo- bata in the United States, was until recently known as Helobata striata (Brulle). Hansen (1991) noted that the latter name was preoccupied by Hydrophilus striatus Say, 1825 (= Berosus striatus) and therefore was a pri- mary homonym. The next available name was Helobata larvalis (Horn), 1873. The distribution of this species was reported (as H. striata) by Spangler and Cross (1972) to range from Buenos Aires, Argentina, north through the West Indies, Central America, Mexico, and along the Gulf Coast to Louisiana and Florida in the United States. Records in both North and South Carolina by Brigham et al. (1982) extended the known distribution northward from Florida. Testa and Lago (1994) listed this species from Texas, but because no precise locality data were given for Texas and no other references have been found citing H. larvalis in Texas, we are providing distributional data. Our records extend the known distribution of this beetle westward into Texas as far as San Patricio and Gonzales Counties (Map 1).

Young (1954) stated "The peculiar structure of the expanded sides of the body suggests that this insect lives on the surface of submerged vegetation, logs, and other objects in much the manner of a limpet." He also stated that it occurs in brackish as well as freshwater. Information gathered in the present studies agrees with his observations. Specimens of Helobata lar\>alis collected from the Anahuac National Wildlife Refuge marsh site in Chambers County,

Vol. 107, No. 1, January & February, 1996

57

Texas (discussed under Hydrobiomorpha castd) were found clinging to the underside of floating, decaying vegetation. One noteworthy specimen was a female with the egg case attached beneath the abdomen as described by Span- gler and Cross (1972), who also described the eggs and first instar larva of this species. Eighteen specimens are reported here from five Texas counties.

TEXAS RECORDS. Chambers Co.: Anahuac National Wildlife Refuge, 4.9 km SE of Visitor Info Booth, marsh, 30 Jun 1993, 2 adults; 13 Jul 1993; 20 Nov 1993; 9 Apr 1994; 25 May 1994; 15 Jun 1994, adult with egg case; 12 Jul 1994; 21 Nov 1994, RCV. Anahuac National Wildlife Refuge, at light near entrance, 20 Sep 1993, RCV. Gonzales Co.: Palmetto St. Park, 7 Jun 1969, 2 adults, Board & Hafernik. Leon Co.: Flynn, 8 km N at sand dune at UV light, 24 May 1994, W.B. Godwin & E.G. Riley. Montgomery Co.: The Woodlands, 1-2 Aug 1977; 2 Jun 1979, J.E. Wappes. San Patricio Co.: Lake Corpus Christi State Park, 9 Jun 1969, Board & Hafernik. Welder Wildlife Refuge, black light, 28 Jun 1969, 2 adults, Board & Hafernik.

n
A Dibolocelus ovatus A Hydrobiomorpha casta • Helobata larvalis O Sperchopsis (esseliata • Hopenus planatus O Suphis inflalus
L]

Map 1. County records lor beetles

newly reported from Texas.

58 ENTOMOLOGICAL NEWS

ACKNOWLEDGMENTS

We would like to thank the personnel at The Nature Conservancy of Texas, Anahuac National Wildlife Refuge, and the J.D. Murphree Wildlife Management Area, for allowing us to collect aquatic insects and for furthering research in the area of aquatic ecology. Special thanks go to Jim Bergan, Gulf Coast Steward, and Chris Robinson, Roy E. Larsen Sandyland Sanctuary Manager, for their support. Funding for travel and expenses to the Runnel's Family Mad Island Preserve was provided by The Nature Conservancy of Texas. Funding for travel and expenses to Anahuac National Wildlife Refuge and the J.D. Murphree Wildlife Management Area was pro- vided by Jim Olson, TAMU Department of Entomology. We are most grateful for this funding. We would also like to thank Sam Testa, USDA-ARS, and Gil Challet, Orange County, CA, Mos- quito Control District, for help with specimen identification. We are very indebted to Horace Burke and Robert Wharton, TAMU Department of Entomology, Merrill Sweet, TAMU Depart- ment of Biology, and anonymous reviewers for their helpful comments on our manuscript. Also, Edward G. Riley, assistant curator of the TAMU Department of Entomology Insect Collection, allowed us free access to the collection, for which we are very grateful. Last, but far from least, we want to sincerely thank our good friends, William B. Godwin and James Randall Gibson, for allowing us to include some of the specimens that they collected.

LITERATURE CITED

Archangelsky, M. and M.E. Durand. 1992. Description of the preimaginal stages of Dibolo-

celus ovatus (Gemminger and Harold, 1868) (Coleoptera, Hydrophilidae: Hydrophilinae).

Aquat. Insec. 14(2): 107-116. Arnett, R.H., Jr. 1973. The beetles of the United States. Amer. Entomol. Inst., Ann Arbor,

Michigan. 1,112 pp. Arnett, R.H., Jr. (ed.) 1983. Checklist of the beetles of North and Central America and the West

Indies. Flora and Fauna Publ's., Gainesville, Florida. 2,173 pp. Bousquet, Y. (ed.) 1991. Checklist of beetles of Canada and Alaska. Research Branch Agric.

Canada, Ottawa, Ontario. 430 pp. Brigham, A.R., W.U. Brigham and A. Gnilka (eds.) 1982. Aquatic insects and oligochaetes of

North and South Carolina. Midwest Aquatic Enterprises, Mahomet, Illinois. 837 pp. I! mile, A. 1841. Famille des Hydrophiliens, famille des Helophoriens. In d'Orbigny, A. (ed.),

Voyage dans 1'Amerique Meridionale. Vol 6, Part 2, Insectes. Paris, Strassbourg. pp. 57-60. Crotch, G.R. and M.A. Cantab. 1873. Revision of the Dytiscidae of the United States. Trans.

Am. Entomol. Soc. 4: 383-424.

Fall, H.C. 1927. A new genus and species of Dytiscidae. J. N.Y. Entomol. Soc. 35: 177-178. Fernandez, L.A. and A.O. Bachmann. 1987. Revision del genero Helobata Bergroth

(Coleoptera: Hydrophilidae). Rev. Soc. Entomol. Argent. 44(2): 149-159. Folkerts, G.W. and L.A. Donavan. 1974. Notes on the ranges and habitats of some little-known

aquatic beetles of the southeastern U.S. (Coleoptera: Gyrinidae, Dytiscidae). Coleopt. Bull.

28(4): 203-208. Foster, R.E. 1972. A survey of aquatic beetles in the city of Nacogdoches, Texas, and environs.

M.S. Thesis, Stephen F. Austin State University, Nacogdoches, Texas. 44 pp.

Vol. 107, No. 1, January & February, 1996 59

Gemminger, M. and E. Harold. 1868. Catalogous Coleopterorum hucusque descriptorum syn- onymicus et systematicus. Tom II. Monachii. pp. 425-978.

Hansen, M. 1991. The hydrophiloid beetles: phylogeny, classification and a revision of the gen- era (Coleoptera: Hydrophiloidea). Biol. Skr. K. Dan. Vidensk. Selsk. 40: 1-367.

Hilsenhoff, W.L. 1987. Effectiveness of bottle traps for collecting Dytiscidae (Coleoptera). Coleopt. Bull. 41(4): 377-380.

Horn, G.H. 1873. Revision of the genera and species of the tribe Hydrobiini. Proc. Am. Phil. Soc. 13: 118-137.

Horn, G.H. 1876. Synoptic tables of some genera of Coleoptera with notes and synonymy. Trans. Am. Entomol. Soc. 5: 246-252.

Horn, G.H. 1890. Notes on some Hydrobiini of Boreal America. Trans. Am. Entomol. Soc. 17: 237-278, 2 pis.

Jacquelin DuVal, P.N.C. 1856. Coleoptera. In de la Sagra, M.R. (ed.), Historic physique, poli- tique et naturelle de Tile de Cuba. Animaux Articules, Insecta. Paris. 136 pp.

Kirk, V.M. 1969. A list of beetles of South Carolina: Part 1 - Northern Coastal Plain. Tech. Bull. S.C. Agric. Exp. Stn. 1033: 1-124.

Kirk, V.M. 1970. A list of the beetles of South Carolina: Part 2 - Mountain, Piedmont and South- ern Coastal Plain. Tech. Bull. S.C. Agric. Exp. Stn. 1038: 1-117.

Knisch, A. 1921. Uber die Gattung Hydrocydus Sharp (Coleoptera: Hydrophilidae sp. 9). Ento- mol. Anzeiger 1(8): 100-107.

Knisch, A. 1924. Hydrophilidae. In Coleopterorum Catalogus XIV, pars 79. W. Junk, Berlin. 306 pp.

LeConte, J.L. 1855. Synopsis of the Hydrophilidae of the United States. Proc. Acad. Nat. Sci. Phila. 7: 356-375.

LeConte, J.L. 1862. Classification of the Coleoptera of North America. Part 1. Smithson. Misc. Collect. 3(136): XXV + 208 pp, figs.

LeConte, J.L. 1863. New species of North American Coleoptera. Part 1. Smithson. Misc. Col- lect. 6(167): 1-86.

Michael, A.G. and J.F. Matta. 1977. The insects of Virginia No. 12, The Dytiscidae of Virginia (Coleoptera: Adephaga). Res. Div. Bull. Va. Polytech. Inst. State Univ. 124: 1-53.

Mouchamps, R. 1959. Remarques concernant les genres Hydrobiomorpha Blackburn et Neohy- drophilus d'Orchymont (Coleopt. Hydrophilides). Bull. Ann. Soc. Roy. Entomol. Belg. 95: 295-335.

d'Orchymont, A. 1911. Contribution a 1'etude des genres Stemolophus Solier, Hydrophilus Leach, Hydrous Leach. Mem. Soc. R. Entomol. Belg. 19: 53-72, 1 pi., 19 figs.

d'Orchymont, A. 1928. Catalogue of Indian insects, Part 14 - Palpicornia. Government of India, Central Publ. Branch, Calcutta, India. 146 pp.

Richmond, E.A. 1962. The flora and fauna of Horn Island, Mississippi. Gulf Res. Rep. 1(2): 59- 106.

Say, T. 1835. Descriptions of new North American coleopterous insects, and observations on some already described. Boston J. Nat. Hist. 1(2): 151-203.

Schwarz, E.A. and H.S. Barber. 1918. Two new hydrophilid beetles. Proc. Entomol. Soc. Wash. 19(1-4): 129-135.

Sharp, D. 1882-1887. Insecta. Coleoptera, (Haliplidae, Dytiscidae, Gyrinidae, Hydrophilidae, Heteroceridae, Parnidae, Georissidae, Cyathoceridae, Staphylinidae). In Godwin, F.D. and O. Salvin (eds.), Biologia Centrali-Americana 1(2): 1-144.

60 ENTOMOLOGICAL NEWS

Smetana, A. 1988. Review of the family Hydrophilidae of Canada and Alaska (Coleoptera).

Mem. Entomol. Soc. Can. 142: 1-316. Spangler, P.J. 1961. Notes on the biology and distribution of Sperchopsis tessellatus (Ziegler)

(Coleoptera: Hydrophilidae). Coleopt. Bull. 15: 105-112. Spangler, PJ. 1973a. The bionomics, immature stages, and distribution of the rare predacious

water beetle, Hope rius planatus (Coleoptera: Dytiscidae). Proc. Biol. Soc. Wash. 86(36): 423-

434. Spangler, P.J. 1973b. A description of the larva of Hydrobiomorpha casta (Coleoptera:

Hydrophilidae). J. Wash. Acad. Sci. 63(4): 160-164.

Spangler, P.J. and J.L. Cross. 1972. A description of the egg case and larva of the water scav- enger beetle, Helobata striata (Coleoptera: Hydrophilidae). Proc. Biol. Soc. Wash. 85(35):

413-418. Spangler, P.J. and G.W. Folkerts. 1973. Reassignment of Colpius inflatus and a description of

its larva (Coleoptera: Noteridae). Proc. Biol. Soc. Wash. 86(43): 501-510. Testa, S., Ill and P.K. Lago. 1994. The aquatic Hydrophilidae (Coleoptera) of Mississippi. Miss.

Agric. For. Exp. Stn. Tech. Bull. 193: 1-71. Warren, M.L., Jr. 1985. Notes on distribution and habitat of Sperchopsis tessellatus (Coleoptera:

Hydrophilidae) in Kentucky. Entomol. News 96(1): 43-44.

White, C.E., F.N. Young and N.M. Downie. 1985. A checklist of the aquatic Coleoptera of Indi- ana. Proc. Indiana Acad. Sci. 94: 357-369. Winters, F.C. 1926. Notes on the Hydrobiini (Coleoptera: Hydrophilidae) of Boreal America.

Pan-Pacif. Entomol. 3(2): 49-58. Wooldridge, D.P. 1967. The aquatic Hydrophilidae of Illinois. Trans. 111. State Acad. Sci. 60(4):

422-431.

Young, F.N. 1954. The water beetles of Florida. Univ. Fla. Publ. Biol. Sci. Ser. 5(1): 1-238. Ziegler, D. 1844. Descriptions of new North American Coleoptera. Proc. Acad. Nat. Sci. Phila.

2: 43-47.

Vol. 107, No. 1, January & February, 1996 61

THE MAYFLIES (EPHEMEROPTERA) OF NORTH AMERICA ONLINE1

W.P. McCafferty2

ABSTRACT: A continually updated, easy-to-use accounting of the Ephemeroptera of Canada, Mexico, and the continental United States is accessible on the World Wide Web. Distributional and nomenclatural information accompanies the comprehensive listing of species and subspecies. Documentation may be accessed directly via the Mayfly Central home page URL.

The first comprehensive accounting of the mayflies of North America is found in Eaton's (1883-88) monograph of the world Ephemeroptera, wherein he treated 92 nominal species. Next, Traver (1935) provided a descriptive treatment of all species known from north of Mexico. She included 546 species. Of those, however, only 423 are still considered valid. Updated checklists of species north of Mexico were later provided by Edmunds and Allen (1957) and Edmunds (1962). Edmunds et al. (1976) tabulated all North American species within treatments of each of the genera recognized at that time. Most recently, McCafferty (1996) provided an updated treatment of species found in North America, accounting for the considerable nomenclat- ural and revisionary changes that have taken place since 1976, and at the same time providing a complete index to all names that previously have been used for North American species.

Published accountings of any large faunas suffer from the fact that they are usually out-of-date by the time they become available. The modern elec- tronic media, however, offer the ideal solution to this dilemma. The main pur- pose of this note is to announce the placement of a complete and continually updated accounting of the mayflies of North America on the World Wide Web. This web version not only will be regularly updated as new information is published, but it will be universally accessible for ready reference because of the client/server technology it incorporates and the platform-independence inherent in the web, i.e., any computer format with appropriate browser soft- ware can use it without downloading or decoding. Browser functions will also allow search and find operations within the document so that, for example, taxonomic names or any combinations thereof may be easily searched, and other data such as geographic regions or current applications of old names pre- sent in the literature may be accessed. For further discussion of the operation and advantages of the World Wide Web, see, e.g., Hayes (1994) and VanDyk (1995).

1 Received October 23, 1995. Accepted October 29, 1995.

2 Department of Entomology, Purdue University, West Lafayette, IN 47907.

ENT. NEWS 107(1): 61-63, January & February, 1996

62 ENTOMOLOGICAL NEWS

"The Mayflies of North America" may be located on the World Wide Web via the Mayfly Central home page URL, which is

http://www.entm.purdue.edu/entomology/mayfly/mayfly.html

Contents of the document are as follows: The current and last dates of cov- erage, the basis of the initial data, and the rationale for the treatment are given for general information purposes. User input is solicited, and users have the opportunity to communicate directly over the internet with Mayfly Central from within the "The Mayflies of North America" by using a simple select function. Any latest changes to the fauna, its nomenclature, or distribution are highlighted, and changes that are anticipated for the near future are also pre- viewed. A section on how to read "The Mayflies of North America" includes a color-coded map of North America (Canada, Mexico, and continental United States) with the six broad geographic regions, adapted from McCafferty and Waltz (1990), that are cited for each species, and a complete explanation of the presentation of the information and how to interpret all other non-valid names that appear with the species. A separate listing of the higher classification of the Ephemeroptera of North America includes suborders, infraorders, super- families, families (and recent equivalents), and genera. These are presented in phylogenetic order, at least to the family level, as presented by McCafferty (1991) and modified by McCafferty and Wang (1994) and Wang and McCaf- ferty (1995). Conveniently, the treatments of any family or any genus in the species list can be accessed by simply selecting the name in the higher classi- fication list.

Finally, in "The Mayflies of North America," the entirely alphabetical list of species is given, listed first by family, and then by genus. The initial edition of the list contains 21 families, 84 genera, and 673 valid species and sub- species. Indented under each valid name are all other names that have histori- cally referred to that species or subspecies in the literature, along with an indication of why the name is subordinate, i.e., if it is a synonym, homonym, misspelling, different combination, or invalid replacement. All names, both valid and subordinate, are accompanied by the author of the name (not reviser) and the official date of publication of the name.

Treatments of the Ephemeroptera of other major geographic regions of the world are being planned as additions to the database of information avail- able from Mayfly Central. Such electronic cataloguing certainly marks a new era of taxonomic services. Not only will non-specialists involved in ecology, surveys, and biodiversity be able to track name changes and new faunistic data, but curators of collections will have access to current data invaluable for managing their collections.

Vol. 107, No. 1, January & February, 1996 63

ACKNOWLEDGMENTS

1 would like to thank all North American ephemeropterists for their contributions to the tax- onomy and distribution of North American mayflies, but in particular I would like to mention those people who have worked closely with me in formulating the electronic version of "The Mayflies of North America." These include George Edmunds, Carlos Lugo-Ortiz, Arwin Provon- sha, Pat Randolph, Bob Waltz, and Tianqi Wang. I would also like to thank Carl Geiger and Elizabeth Thelen for their technical assistance. This paper has been assigned Purdue Agricultural Research Program Journal Number 14845.

LITERATURE CITED

Eaton, A.E. 1883-88. A revisional monograph of recent Ephemeridae or mayflies. Trans.

Linn. Soc. Lond., 2nd Ser.-ZooI. 3: 1-352. Edmunds, G.F., Jr. 1962. The type localities of the Ephemeroptera of North American north of

Mexico. Univ. Utah Biol. Ser. 12(5): viii + 1-39. Edmunds, G.F., Jr. and R.K. Allen. 1957. A checklist of the Ephemeroptera of North American

north of Mexico. Ann. Entomol. Soc. Am. 50: 317-324.

Edmunds, G.F., Jr., S.L. Jensen and L. Berner. 1976. The mayflies of North and Central Amer- ica. Univ. Minn. Press, Minneapolis.

Hayes, B. 1994. The World Wide Web. Am. Sci. 82: 416-420. McCafferty, W.P. 1991. Toward a phylogenetic classification of the Ephemeroptera (Insecta): a

commentary on systematics. Ann. Entomol. Soc. Am. 84: 343-360.

McCafferty, W.P. 1996. The Ephemeroptera species of North America and index to their com- plete nomenclature. Trans. Am. Entomol. Soc., in press. McCafferty, W.P. and R.D. Waltz. 1990. Revisionary synopsis of the Baetidae (Ephemeroptera)

of North and Middle America. Trans. Am. Entomol. Soc. 1 16: 769-799. McCafferty, W.P. and T.-Q. Wang. 1990. Relationships of the genera Acanthametropus,

Analetris, and Siphluriscm, and re -evaluation of their higher classification (Ephemeroptera:

Pisciforma). Gr. Lakes Entomol. 27: 209-215. Traver, J.R. 1935. Part II, Systematic, pp. 239-739. In: J.G. Needham, J.R. Traverand Y.-C. Hsu

[eds.], The biology of mayflies with a systematic account of North American species Comstock

Publ. Co., Ithaca, N.Y. VanDyk, J.K. 1995. Entomologists and the internet: it's time to get online. Am. Entomol. 41:

162-168. Wang, T.-Q. and W.P. McCafferty. 1995. Relationships of Arthropleidae, Heptageniidae, and

Pseudironidae (Ephemeroptera: Heptagenioidea). Entomol. News 106: 251-256.

64 ENTOMOLOGICAL NEWS

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MARCH & APRIL, 1996

NO. 2

462 (

ENTOMOLOGICAL NEWS

Ascriptions of female, nymph, and variations in male characters of stonefly Leuctra szczytkoi

(Plecoptera: Leuctridae)

R. E. De Walt, B. P. Stark 6 1

New field observations on burrowing in Ephemerop-

tera from around the world G.F. Edmunds, Jr., W.P. McCafferty 68

Density and diversity of non-target insects killed

by suburban electric insect traps T.B. Frick, D.W. Tallamy 77

An atypical larval color form of Baetis intercalaris (Ephemeroptera: Baetidae) from Pennsylvania and southeastern Oklahoma

R.D. Waltz, D.E. Baumgardner, J.H. Kennedy 83

A new Peruvian musapsocid genus and species (Psocop-

tera: Musapsocidae) A.N.G. Aldrete, E.L. Mockford 88

Attracting parasitic flies (Diptera: Phoridae) to

injured workers of giant ant Dinoponera gigantea

(Hymenoptera: Formicidae) AJ.S.-Costa, P.R.S. Moutinho 93

Redescription and reclassification of South American mayfly Melanemerella brasiliana (Ephemeroptera: Leptophlebiidae) T.-Q. Wang, W.P. McCafferty 99

New information on New World Physocephala (Diptera: Conopidae)

Notes on spittlebug genus Ectemnonotum (Homop- tera: Cercopidae)

Sidney Camras 104

Ai-Ping Liang 113

SCIENTIFIC NOTE:

First report of Chauliognathus (Coleoptera:

Cantharidae) larvae in excavated shoots of

Pinus sylvestris. R.D. Waltz, T. McCay-Buis 119

BOOKS RECEIVED AND BRIEFLY NOTED

120

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Vol. 107, No. 2, March & April, 1996 61

DESCRIPTIONS OF THE FEMALE, NYMPH,

AND VARIATION IN MALE CHARACTERS

OF THE STONEFLY LEUCTRA SZCZYTKOI

(PLECOPTERA: LEUCTRIDAE)1

R. Edward DeWalt2, Bill P. Stark3

ABSTRACT: Leuctra szczytkoi until recently was known only from the holotype male collected from Schoolhouse Springs of northcentral Louisiana. Collections in the late fall and winter of 1993- 1995 provided additional specimens for describing the variation in the male characters and primary descriptions of the female and nymph of this species of the Leuctra ferruginea species group. Males are separated from all others in the group by a combination of a prominent subapical specil- lium spine, paraprocts and specillia being subequal, and by a triangular specillium. Females were distinguished by a shallow u-shaped notch on the subgenital plate. Nymphs apparently differ from others in the group by lacking sternal bristles anterior to segment 8. Leuctra szczytkoi is endemic to central and northcentral Louisiana in slow-flowing, lowland headwater streams of the Red River drainage.

Leuctra szczytkoi Stark and Stewart (Stark and Stewart, 1981) is a member of the L. ferruginea (Walker) species group. Members of this group have taper- ing specillia, often with one or more subapical spines of various lengths. Other members include L. paleo Poulton and Stewart, L. crossi James, L. ferruginea (Walker), L. rickeri James, and L. alabama James (James, 1974 and 1976; Poulton and Stewart, 1991). Since the original description of L. szczytkoi from a male specimen collected in Louisiana (Stark and Stewart, 1981), no addi- tional records of this species have been published. Attempts to collect addi- tional specimens initially concentrated around the March collection date and the remote Schoolhouse Springs site in Jackson Parish where the holotype was collected. This site, now owned by the Nature Conservancy, was described by Morse and Barr (1990).

A series of males, females, and nymphs from several Louisiana streams south of the type locality were recently collected by R. E. DeWalt. These col- lections enable the authors to describe the female and nymphal stages and also allow for additional information on variation in the male.

Leuctra szczytkoi Stark and Stewart

Leuctra szczytkoi Stark and Stewart, 1981, holotype male, Schoolhouse Springs, Jackson Par- ish, Louisiana.

1 Received August 31, 1995. Accepted October 16, 1995.

2 Illinois Natural History Survey, 607 E. Peabody Dr., Champaign, IL 61820.

3 Department of Biological Sciences, Mississippi College, Box 4045, Clinton, MS 39058.

\

T. NEWS 107(2): 61-67, March & April, 1996

62 ENTOMOLOGICAL NEWS

Male. - Forewing length 6-7 mm. Tergum 7 with at most slightly thickened process on the mid-anterodorsal line. Tergum 8 with basal sclerotized band expanded medially into at most slightly elevated process which varies from rounded to triangular in outline (Fig. 1). Vesicle on sternum 9 triangular in outline (Fig. 2). Paraprocts slightly shorter than specillia, ventrolateral aspect with weak basal keel (Figs. 1, 3). Ventrobasal aspect of specillia angular and giving nearly pyramidal appearance, medial edges divergent.

Female. - Forewing length 8 mm. Sclerites on sterna 7 and 8 connected by pair of obscure lateral bridges. Lobes of subgenital plate truncate, notch shallow and u-shaped. Intersegmental membrane of sternum 9 with pair of small, basal sclerites (Fig. 4).

Nymph. - Body length 5-6 mm. General color pale brown, occiput with obscure mottled areas (Fig. 5). Post-ocular bristles 2, lower frontal and anterior clypeal bristles 1 each. Right and left anterior pronotal bristles 6-7 each, length variable; 2 posterior pronotal bristles located forward of posterior angles. Anterolateral mesonotal tuft with 8 short bristles; 6 outer marginal mesonotal bristles located at wing pad base; pair of fine bristles on posterodorsal margin of mesonotum; inner marginal mesonotal bristles absent (Fig. 5).

All terga of abdomen with band of short bristles extending to near pleura; abdominal sterna 8 and 9 each with single long posterior bristle in lateral aspect; sternal bristles absent on more ante- rior segments (Fig. 6). Basal cereal segments with apical whorls of moderately long bristles, mesal segments with progressively longer bristles through segment 14; apical segments with few, short bristles in apical whorls. Cereal segments present 20-22 (Fig. 7).

Distribution and ecology. -Additional collections (Table 1) seem to limit the geographical distribution of L. szczytkoi to lower elevations (21 to 46 m asl) of Omernik's (1987) South Central Plains Ecoregion (SCPE) in central and northern Louisiana (Fig. 8). Collections to date have been from west of the Mississippi River in 1 to 5 m-wide, first and second order drainages of the Red River basin (Fig. 8). Efforts to locate this species in the upland areas further west of recent localities, and to the east of the Mississippi River, have been unsuccessful. Leuctra rickeri and possibly an undescribed species in the group have recently been collected from Washington Parish, in eastern Louisiana.

Slopes of the streams in the vicinity of recent collections were 1.3 m/km for Loving Creek, 1.6 m/km for Jordan Creek, and 2.79 m/km for Beaver Creek. Substrates in these streams consisted of mostly sand, small amounts of fine gravel, and abundant woody debris. Natural riparian vegetation included bald cypress, oaks, shortleaf pine, and various ericaceous shrubs. These streams ex- hibited dark tea-colored water, accumulations of fine brown organic matter, and an abundant aufwuchs (attached microbial) community. Springs were common along the banks of these streams, as described for the type locality by Morse and Barr (1990). These descriptions are also consistent with Hitchcock's (1974) assertion that leuctrids prefer small, slow-flowing streams. The threatened Loui- siana pearlshell mussel, Margaritifera hembeli (Conrad) also occurs at the sites of the 1993-1995 collections (P. D. Johnson, pers. comm.).

The emergence of adults at the sites listed in Table 1 was well under way by late October. Pre-emergent nymphs of L. szczytkoi were collected from leafpacks associated with wood. Exuviae were left near the water's edge on emergent woody substrates. Adults were often collected from just above the water level

Vol. 107, No. 2, March & April, 1996

63

•.'•S-W'-j-' •.••';; •/•.':••; i'v7/-/":,"/,;-;/;. • ,;,. >

l- • v- :-f-.i-?l'vVr'f:' r*.' ',. <

,

fe'q:

f|$-':o ^v^''rV!'!;!-r''.- I

Figs. 1-4. Leuctra szczytkoi, adult features. 1. Male terminalia, dorsal. 2. Male eighth sternite. 3. Male ventrolateral aspect of left specillium (s) and paraproct (p). 4. Female terminalia, ventral.

64

ENTOMOLOGICAL NEWS

Figs. 5-7. Leuctra szczytkoi, nymphal features. 5. Head, pronotum, and mesonotum. 6. abdominal segments 6-10, lateral. 7. Right cercus, lateral.

Vol. 107, No. 2, March & April, 1996

65

on the undersides of wood or from dry leafpacks. Hand picking adults from the stream margin was more effective than using a beating sheet in riparian shrubs. This species may prefer to remain low in the vegetation rather than climb shrubs.

DISCUSSION

Males in this sample had a more rounded lobe on tergum 8, whereas the holotype had a triangular lobe (see Fig. 1 in Stark and Stewart, 1 98 1 ), otherwise the holotype and these additional males were indistinguishable. Leuctra paleo and L. szczytkoi appeared to be indistinguishable using descriptions in the lit- erature (Stark and Stewart, 1 98 1 ; Poulton and Stewart, 1 99 1 ), this coupled with their ranges in the SCPE and emergence beginning in October, necessitated examination of the holotypes. Leuctra paleo differed by having a more acute specillium spine, a rounded outline for the specillium, and by having parallel medial sides of the specillium.

Leuctra ferruginea and L. rickeri possess only small, and sometimes incon- spicuous, spines atop the specillium. Their paraprocts are shorter than the specillia. Leuctra alabama may possess these spines, but its paraprocts and specillia are subequal in length (James, 1974 and 1976).

Females in this sample were also distinct from other members of the ferruginea group. Poulton and Stewart (1991) show that subgenital plate lobes

Leuctra szczytkoi Distribution

RedR.

A Type locality • New localities

Boundary of South Central Plains

1 . Schoolhouse Springs

2. Beaver Creek

3. Jordon Creek

4. Loving Creek

Fig. 8. Distribution of Leuctra szczytkoi in Louisiana. SCPE = South Central Plains Ecoregion.

66

ENTOMOLOGICAL NEWS

of L. paleo are rounded, with an evenly curving median notch. James (1974, 1976) illustrates other members of the group as having truncate to broadly rounded lobes of the subgenital plate with deep parabolic notches.

Nymphs were quite similar to L.ferruginea and could be determined as this species by using keys in Harper and Hynes (1971). The two species appeared to be distinct in the nymphal stage because L. szczytkoi lacked sternal bristles anterior to segment 8 (see Fig. 17 in Harper and Hynes, 1971). Due to the frag- ile nature of these bristles, a larger sample size of mature nymphs would be needed to confirm this character.

Leuctra szczytkoi emerged in October, with most nymphs having transformed shortly thereafter. The scattered January records and the late March collection date for the holotype suggested that L. szczytkoi exhibited an extended emer- gence throughout the fall and winter. In contrast, most species of the L.ferruginea group emerge in spring and summer (Harper and Hynes, 1971; James, 1974 and 1976).

The Louisiana Department of Wildlife and Fisheries, Natural Heritage Pro- gram, has designated this species as SI, meaning that it is critically imperiled due to its extreme rarity, being known from five or fewer extant populations (S. H. Shively, pers. comm.). This ranking was given because the only published record of its occurrence was from Schoolhouse Springs. The status might well be downgraded to S3, a species found in a restricted region of the state, but locally abundant where found.

Table 1 . Localities and collection information for Leuctra szczytkoi collected from Louisiana. N = number of nymphs collected.

Dates Latitude Transect

Stream Parish D-M-Y Longitude Range, Section Specimens

Schoolhouse Springs Jackson 30-111-73 32°28.63'N T17NR1WS12 Cf

92°25.48'W

Beaver Creek Grant 24-X-93 31°36.60'N T7N R2W S5 Cf 3N

92°36.10'W

30-X-93 2Cf39

24-1-94 9

Jordan Creek Grant 30-X-93 31°31.17'N T6NR2WS12 5Cf 59 ION

92°31.79'N

8-1-95 Cf

Loving Creek Rapides 30-X-93 31°12.00'N T3N R2W S28 Cf 2N

92°34.40'W

7-1-95 Cf 9

Vol. 107, No. 2, March & April, 1996 67

Voucher specimens have been deposited in the National Museum of Natural History, in the Louisiana State University Insect Collection, and in the author's personal collection.

ACKNOWLEDGMENTS

We thank Nancy Adams, National Museum of Natural History, Smithsonian Institution, for lending types of L. szczytkoi and L paleo for study. J. B. Chapin and V. L. Moseley provided reviews on early drafts. This study was partially funded by the Department of Zoology and Physi- ology, Louisiana State University.

LITERATURE CITED

Harper, P. P., and H. B. N. Hynes. 1971 . The Leuctridae of eastern Canada (Insecta: Plecoptera).

Can. J.Zool. 49:915-920. Hitchcock, S. W. 1974. Guide to the insects of Connecticut. Part VII. The Plecoptera or stoneflies

of Connecticut. State Geological and Natural History Survey of Connecticut 107. James, A. M. 1974. Four new species of stoneflies in North America (Plecoptera). Ann. Entomol.

Soc. Amer. 67:964-966. James, A. M. 1976. Two new species of Leuctra, with notes on the ferruginea group (Plecoptera:

Leuctridae). Ann. Entomol. Soc. Amer. 69:882-884. Morse, J. C., and C. B. Barn 1 990. Unusual caddisfly (Trichoptera) fauna of Schoolhouse Springs,

Louisiana, with description of a new species of Diplectrona (Hydropsychidae). Proc. Entomol.

Soc. Wash. 92:58-65. Omernik, J. M. 1987. Ecoregions of the conterminous United States. Ann. Assoc. Amer. Geogr.

77:118-125. Poulton, B. C., and K. W. Stewart. 1991. The stoneflies of the Ozark and Ouachita Mountains

(Plecoptera). Mem. Amer. Entomol. Soc. 38:1-1 16. Stark, B. P., and K.W. Stewart. 1981. Leuctra szczytkoi a new stonefly from Louisiana (Plecoptera:

Leuctridae). Entomol. News 92:91-92.

68 ENTOMOLOGICAL NEWS

NEW FIELD OBSERVATIONS ON BURROWING IN EPHEMEROPTERA FROM AROUND THE WORLD1

George F. Edmunds, Jr.2, W. P. McCafferty3

ABSTRACT: New observations on burrowing behavior of mayfly larvae are given for the lepto- phlebiids Paraleptophlebia packi and P. bicornuta in North America, and Jappa kutera in Austra- lia; for the potamanthids Potamanthus idiocerus in Taiwan, and P. formosus and Rhoennanthus speciosus in Malaysia; for the polymitarcyids Proboscidoplocia spp. in Madagascar, Afroplocia sampsoni in South Africa, and Ephoron album in North America; and for the ephemerids Ephemera simulans and Litobrancha recurvata in North America, and Palingenia fuliginosa in east Europe. Paraleptophlebia packi forms burrows in silt, whereas P. bicornuta is an interstitial dweller. Potamanthus idiocerus and R. speciosus are the first species of Potamanthidae known to form burrows in silt; however, P. formosus is more typical of the family in that it is an interstitial dweller. Silt burrows made by Leptophlebiidae and Potamanthidae are formed along a rock interface and are never U-shaped, but those formed by advanced burrowers in the Polymitarcyidae and Ephemeridae are independent of rocks and often U-shaped. New evidence of burrowing in plesiotypic polymitarcyid lineages with flat-bodied larvae, represented by Proboscidoplocia and Afroplocia, is provided. Ephoron album is a highly flexible burrower; its larvae form burrows in depositional substrates, but are interstitial dwellers in erosional substrates. Palingenia fuliginosa is the first non-polymitarcyid burrower to be found burrowing in wood.

Many mayflies live within the substrate of bodies of freshwater during at least part of their larval life. Some inhabit interstitial areas of substrate tempo- rarily as very young larvae (see e.g., Coleman and Hynes 1970, Williams 1984), evidently acquiring some protection in such habitats during this part of their lives, but otherwise showing no particular adaptations for subbenthic habitats. Although these mayflies may be associated with hyporheic nurseries as early instars, they are generally surface benthos. Some sprawler and clinger mayfly larvae are known to move vertically through the substrate on a daily basis (e.g., see Glozier and Gulp 1989), and some of these may occur under the buried undersides of stones or other surface substrates especially during daylight hours. Many mayflies are associated with fine sand or sand/silt habitats, and are no- table in lotic environments with shifting sand substrates. Those known as psam- mophilous mayflies typically show adaptations for living on, or partially to completely buried within, the sandy substrate (see e.g., McCafferty 1991b).

The above mentioned mayflies, although they may move into interstitial areas temporarily or may settle in fine substrates, have not traditionally been known as burrowing mayflies. The term burrowing, when applied to Epheme- roptera, has generally been applied to those mayflies that demonstrate adapta- tions for excavating and residing more-or-less permanently within substrates

1 Received August 3, 1995; Accepted September 9, 1995.

2 Department of Biology, University of Utah, Salt Lake City, UT84112.

3 Department of Entomology, Purdue University, West Lafayette, IN 47907.

ENT. NEWS 107(2): 68-76, March & April, 1996

Vol. 107, No. 2, March & April, 1996 69

that include coarse sand, silt, sand/marl, clay, mixed gravel, wood, and fresh- water sponges.

Bae and McCafferty (1994) indicated that there were two main categories of burrowing mayflies, based on their ecology and behavior. Those that have been designated as interstitial dwellers by Bae and McCafferty (1995) actively burrow in interstices or available crevices, and although capable of excavating, they are limited in their ability to manufacture and maintain actual tunnels, or burrows, within the substrate. Burrowers in coarse sand and mixed gravel, such as Dolania americana Edmunds and Traver (e.g. , see McCafferty 1975, Edmunds et al. 1976) and Anthopotamus verticis (Say) (see Bae and McCafferty 1994) generally fit the interstitial dweller category. Burrow dwellers (Bae and McCafferty 1995), on the other hand, construct and dwell within walled, some- times U-shaped burrows in finer and more compacted materials or solid sub- strates. The most detailed study of such burrowers was provided by Keltner and McCafferty (1986) in their videomacroscopic study of Hexagenia limbata (Serville) and Pentagenia vittigera (Walsh).

Burrowing, as it is known in Ephemeroptera, is also associated with one particular evolutionary lineage of mayflies known as the infraorder Lanceolata (McCafferty 199 1 a). This grouping includes the superfamilies Leptophlebioidea, Behningioidea, and Ephemeroidea. Fossorial adaptations are most highly evolved in the Ephemeroidea.

Mandibular tusks are structural adaptations most commonly associated with burrowing mayfly larvae. Tusks are present in all ephemeroid mayfly larvae, and only in a few cases have become secondarily reduced (McCafferty and Edmunds 1973, McCafferty and Gillies 1979, Bae and McCafferty 1991 ). Bur- rowing is not widespread in the large superfamily Leptophlebioidea, but tusks are present in larvae of most of the few leptophlebioids that are known to bur- row. Leptophlebioid mandibular tusks are not homologous with ephemeroid tusks (Needham et al 1935). Mandibular tusks are entirely absent in the behningioid burrowers. Bae and McCafferty (1995) recently treated the origin of Ephemeroptera tusks and their radiation and structural adaptations in rela- tion to the evolution of burrowing behavior and ecology.

Over 100 literature sources of published information on burrowing in may- flies was reviewed by Bae and McCafferty (1995). The purpose of this paper is to present new field observations on Ephemeroptera burrowing, and to draw pertinent comparisons with previously published data. Many of the new obser- vations were made on foreign collecting expeditions, where time was limited and experimental facilities were not available.

Paraleptophlebia (Leptophlebioidea: Leptophlebiidae)

Within the genus Paraleptophlebia, stream-dwelling larvae of four of the

70 ENTOMOLOGICAL NEWS

western North American species have mandibular tusks. These tusks, however, are not derived from the body of the mandible as in Ephemeroidea, but rather from the incisors of the mandibles. The habitats off! bicornuta (McDunnough) and P. packi (Needham) were treated somewhat by Lehmkuhl and Anderson (1971) and Needham (1927), respectively. We have new observations regarding the behavior of these species: The most abundant tusked Paraleptophlebia spe- cies, P. bicornuta, moves freely through interstices of gravel and cobble sub- strate. Paraleptophlebia packi in Utah, however, maintains long burrows, up to 40 cm in length, along the interface between large boulders and silt deposits. When boulders are disturbed, the burrows collapse, but the burrow tracks along the boulder often remain evident. Our observations thus indicate that both inter- stitial dwelling and a crude type of burrow dwelling exist in Leptophlebiidae with mandibular tusks. Nothing is known of the presumed burrowing habit of P. Helena (Day) or P. zayante (Day) of California.

Jappa (Leptophlebioidea: Leptophlebiidae)

Larvae of the eastern Australia genus Jappa are also known to burrow (see Peters and Campbell 1991, and review by Bae and McCafferty 1995). These larvae do not have mandibular tusks, but instead possess cephalic tusks (elon- gated frontal horns on the head). Bae and McCafferty (1995) regarded these as most analogous with the mandibular tusks of Rhoenanthus (Ephemeroidea: Potamanthidae). Larvae are known to burrow along mud/rock interfaces, and in gravel and sand. The new observation reported here is that in New England National Park N.S.W., larvae of J. kutera Harker burrow along rocks only ca 10-15 cm in diameter, the largest available for burrow interfacing. The habitat of these larvae was a large diffuse spring-saturated area having many rivulets and a mud substrate with moss and other low vegetation.

Potamanthus (Ephemeroidea: Potamanthidae)

Bae and McCafferty (1991) indicated that all genera of the Potamanthidae had been confirmed to burrow (see also review of Bae and McCafferty 1995). A critical laboratory study of the eastern North American species Anthopotamus verticis by Bae and McCafferty (1994) clearly demonstrated the burrowing habit, and therefore substantiated anecdotal and incomplete field observations that had appeared up to that time. This, in part, also refuted the popular notion that potamanthid larvae were typical sprawling benthos because they had flattened bodies. We have made additional observations of burrowing in the family Potamanthidae.

Larvae of P. (Potamanthodes) idiocerus Bae and McCafferty were observed and collected in a silted river in Taiwan. Mature larvae were found in distinct, long burrows, ca 30 cm long. The burrows were at the interface of silt and

Vol. 107, No. 2, March & April, 1996 71

boulders. When boulders were moved the burrows collapsed, but the paths of the burrows on the boulders were evident. The larval microhabitat was similar to that of Paraleptophlebia packi, as reported above. Larvae of P. (Potaman- thodes)formosus Eaton in Korea had been found to live interstitially by Bae (in Bae and McCafferty 1991); however, no details were provided at that time. Additional observations of this species were made from north of Kuala Lumpur, Malaysia. Larvae occurred in stream bottoms with a mix of rocks, gravel, and sand, where they occupied, perhaps exclusively, interstices in gravel beneath moderate to large boulders. Their habit and habitat is evidently similar, at least in part, to that detailed for Anthopotamus in North America by Bae and McCafferty (1994).

Rhoenanthm (Ephemeroidea: Potamanthidae)

The only comprehensive study of burrowing in Potamanthidae (Bae and McCafferty 1994) indicated that the American genus Anthopotamus is an inter- stitial dweller. Observations of Rhoenanthus speciosus Eaton from Sabah indi- cate that mature and nearly mature larvae of this species burrow at the interface of silt and 10-15 cm diameter rocks. This observation, along with the observa- tions of the larvae of P. idiocerus in Taiwan, reported above for the first time, indicate that structural burrows can be formed in silt along the interface of rocks by certain species of Potamanthidae. Technically, this would qualify them as burrow dwellers (sensu Bae and McCafferty 1994).

Proboscidoplocia (Ephemeroidea: Polymitarcyidae)

Proboscidoplocia belongs to the subfamily Euthyplociinae, one of the primi- tive lineages of Polymitarcyidae (McCafferty 199 la) that has dorsoventrally flattened larvae. Very little information on the microhabitat of this subfamily has been available, except for some recent observations of Euthyplocia Hecuba (Hagen) from Costa Rica. Sweeney et al. (1995) reported that larvae of Euthyplocia burrow under small to large cobbles embedded in stream beds with a sandy matrix. Given such substrate type and the fact that filtering setae occur in rows along the mandibular tusks in this genus (Bae and McCafferty 1995), we deduce that these larvae feed within the substrate, similar to that described for Anthopotamus verticis by McCafferty and Bae (1992). An additional obser- vation from this subfamily is of Proboscidoplocia spp. from Madagascar, in- cluding P. sikorai (Vaysierre) and possibly undescribed species. Larvae were collected from the upper 15 cm of sand around the base of cobble. This sug- gests a habit and habitat somewhat similar to that of E. hecuba (see above). We do not know if any of these Euthyplociinae larvae form burrows along the rock interface.

72 ENTOMOLOGICAL NEWS

Afroplocia (Ephemeroidea: Polymitarcyidae)

Another primitive subfamily of Polymitarcyidae is the Exeuthyplociinae (McCafferty 199 la), which consists of two African genera, Afroplocia and Exeuthyplocia. Although Gillies (1980) suggested that larvae of this group may indeed burrow, there have thus far been no actual observations of such. Adding to this distinct possibility is the new observation from the Mooi River in Natal, South Africa, where larvae of Afroplocia sampsoni (Barnard) were kicked from within mixed substrate ranging from silt/sand to small cobble. From this inci- dental data, we do not know whether Afroplocia larvae are interstitial dwellers or burrow dwellers utilizing rock interface, although the absence of pure silt may preclude burrow formation.

Ephoron (Ephemeroidea: Polymitarcyidae)

Bae and McCafferty (1995) reported that Ephoron larvae (subfamily Polymitarcyinae) form and maintain distinct burrows when the substrate is ap- propriate, but can be interstitial dwellers under other substrate conditions. New observations corroborate this flexible range of burrowing. In Utah, E. album (Say) larvae burrow in the clay banks and bottoms of the Jordan River and associated irrigation canals, and appear to form U-shaped burrows typical of many advanced burrowers. When the water level drops, the honeycombed banks are reminiscent of those of Tortopus (another polymitarcyid in the subfamily Campsurinae), as illustrated by Scott etal, (1959). In contrast, E. album larvae from the Green River, where cobbles are embedded in clay, burrow along the clay-rock interface and the burrow is apparently not U-shaped. In erosional areas of the Tippecanoe River in Indiana, E. album larvae have commonly been taken from mixed gravel and cobble substrate, where they exist as interstitial dwellers. In depositional areas of the Tippecanoe River, this same species forms burrows in silt and marl substrates. Ephoron leukon Williamson, a species that cohabits the Tippecanoe River with E. album, is only known from erosional areas where it is an interstitial dweller. Based on collecting data, E. savignyi (Pictet) in southern Africa may also be as flexible as E. album with respect to being an interstitial dweller or burrow dweller.

Ephemera (Ephemeroidea: Ephemeridae)

Among the subfamily Ephemerinae of the Ephemeridae, we have found Ephemera simulans Walker in a variety of habitats. The species occurs in a broad spectrum of streams and lakes throughout much of North America. In Crawfish Creek and the Firehole River in Yellowstone National Park, larvae inhabit loose sand, including small sandy pockets in cavities of volcanic rock,

Vol. 107, No. 2, March & April, 1996 73

ca 2-3 cm in diameter. In the Uintah River in Utah, larvae occur near the stream margin in silt and sand mixture. This species cohabits the river with the burrow- ing ephemerid Hexagenia limbata (Serville), which forms burrows in silt and marl. In Indiana, E. simulans larvae occur mainly in erosional areas of streams with mixed sand and gravel substrates. The species is apparently an interstitial dweller, and our observations support those of Eriksen (1964), who demon- strated in laboratory studies that the species tended to select fine gravel. Al- though the larvae could burrow in a variety of substrate types, the relatively low DO of finer sediments, such as silt, limited this species to substrates with larger interstices (Eriksen 1968). Ephemera danica Miiller in Europe is known to occur in sand and gravel as young larvae and in gravel as mature larvae (Tolkamp and Both 1978). Ephemera vulgata L., in contrast, is known to be a burrow dweller (e.g., Verrier 1956), often in clay substrates.

Litobrancha (Ephemeroidea: Ephemeridae)

The eastern North American burrowing mayfly Litobrancha recurvata (Mor- gan) is a member of the subfamily Hexageniinae, all members of which are known to be burrow dwellers with advanced burrowing behavior (Bae and McCafferty 1995). Classic respiratory studies by Morgan and Grierson (1932) and Morgan and Wilder (1936) were performed on L. recurvata from small sand bottomed streams in Massachusetts. New observations of L recurvata larvae from streams in the upper peninsula of Michigan clearly show them to be U-shaped burrow dwellers in heavy, organically rich silt. Given the fact that Litobrancha larvae have similar structural adaptations to those of the closely related Hexagenia (see Keltner and McCafferty 1986), there can be little doubt that the larvae studied by Morgan and her coworkers were also taken from silt deposits.

Palingenia (Ephemeroidea: Ephemeridae)

Palingenia is a member of the subfamily Palingeniinae of the Ephemeridae. Its members, like those of the Hexageniinae and Pentageniinae, are known to be burrow dwellers exclusively (see Bae and McCafferty 1995). Along with the Per.tageniinae, the Palingeniinae is considered the most apotypic lineage in the fami'y (McCafferty 199 la). Palingenia fuliginosa (Georgi) is a European spe- cies known to burrow in river silt (e.g., Soldan 1978). While collecting in Slovakia, a decayed log of driftwood about 10cm in diameter was broken open to reveal a larva of this species. Although wood burrowing, even in teak and bamboo, is well documented in the subfamily Asthenopodinae (family Poly- mitarcyidae) in the Orient, Africa, and South America (e.g., Vejabhongse 1 937, Hartland-Rowe 1953, Saltier 1967), this is a new and unexpected observation for the family Ephemeridae.

74 ENTOMOLOGICAL NEWS

EVOLUTIONARY IMPLICATIONS

Silt burrows in Potamanthidae and Leptophlebiidae evidently require a rock interface, and they do not appear to be as structurally advanced as the uniformly walled and often U-shaped burrows constructed by the more advanced burrow dwellers in the apotypic lineages of Polymitarcyidae and Ephemeridae (see Bae and McCafferty 1995). Based on phylogenetic relationships (McCafferty 1991a, Bae and McCafferty 1995), interstitial dwelling, which may or may not require a rock interface, may be deduced to be the most primitive type of burrowing. Some close relatives of interstitial dwellers can form burrows. These burrow dwelling larvae apparently require a rock interface for mobility and purchase by the larvae, because they do not have adaptations for moving in silt as are present on the legs of the more advanced burrow dwellers (see Keltner and McCafferty 1986). Such adaptations include, for example, large spurs, expanded tibiae, and developed tibial processes. Primitive burrows formed along rock surfaces represent a likely step in the evolution from interstitial dwelling to burrow dwelling independent of rock surfaces, at least in the Potamanthidae- Ephemeridae lineage.

The more advanced type of burrowing and burrow formation developed independently in the Polymitarcyidae lineage and the Potamanthidae-Ephe- meridae lineage, as detailed by Bae and McCafferty (1995). This dichotomy is evidenced by functional similarities, but adaptive structural differences, in the two lineages. The flat bodied burrowers in the plesiotypic subfamilies Euthyplociinae and Exeuthyplociinae of the Polymitarcyidae, just as the flat- bodied potamanthid larvae of the Potamanthidae-Ephemeridae lineage, are evi- dently interstitial dwellers or primitive burrow dwellers. Observations of Euthyplociinae larvae, at least, indicate that a rock interface is used in burrow- ing, but the observations of sand or sand matrix leaves some doubt as to whether an actual burrow can be maintained, depending on the quality of silt present. Nevertheless, we would not be surprised to find both interstitial dwelling and primitive burrow dwelling, which requires a rock interface, in these groups. An advanced type of burrow dwelling, independent of a rock surface, would seem to be out of the question for these groups because their larvae, like those of the Potamanthidae, demonstrate no adaptations for moving in silt. At least one spe- cies of more advanced Polymitarcyidae (see E. album, above) demonstrates all evolutionary gradations of burrowing habitat and burrow formation. As deduced for the Potamanthidae-Ephemeridae lineage, burrow dwelling along a rock in- terface also could have been the intermediate step in the evolution of more advanced burrowing in the polymitarcyid lineage.

Vol. 107, No. 2, March & April, 1996 75

ACKNOWLEDGMENTS

Research in South Africa was supported by grants to WPM from the South African Foundation for Research Development and the Anglo-American de Beer's Fund. Research in the midwestern USA was supported in part by grants to WPM from the Huron Mountains Wildlife Foundation. Research in other parts of the world were supported by various grants to GFE from the National Science foundation. This paper has been assigned Purdue Agricultural Research Program Journal Number 14701.

LITERATURE CITED

Bae, Y. J. and W. P. McCafferty. 1991. Phylogenetic systematics of the Potamanthidae (Epheme-

roptera). Trans. Am. Entomol. Soc. 117: 1-143. Bae, Y. J. and W. P. McCafferty, 1994. Microhabitat of Antlwpotamus vert ids (Ephemeroptera:

Potamanthidae). Hydrobiol. 288: 65-78. Bae, Y. J. and W. P. McCafferty. 1995. Ephemeroptera tusks and their evolution, pp. 377-403. In:

L. Corkum and J. Ciborowski [Eds.], Current directions in research on Ephemeroptera. Cana- dian Scholars' Press, Toronto. Coleman, M. J. and H. B. N. Hynes. 1 970. The vertical distribution of the invertebrate fauna in the

bed of a stream. Limnol. Oceonogr. 15: 31-40. Edmunds, G. F., Jr., S. L. Jensen and L. Berner. 1 976. The mayflies of North and Central America.

Univ. Minnesota Press, Minneapolis. Eriksen, C. H. 1964. The influence of respiration and substrate upon the distribution of burrowing

mayfly naiads. Verh. Int. Ver. Limnol. 15: 903-91 1.

Eriksen, C. H. 1968. Ecological significance of respiration and substrate for burrowing Epheme- roptera. Can. J. Zool. 46: 93-103. Gillies, M. T. 1980. The African Euthyplociidae (Ephemeroptera) (Exeuthyplociinae, subfam. n.).

Aquat. Insects 2: 217-224. Glozier, N. E. and J. M. Culp. 1989. Experimental investigations of diel vertical movements by

lotic mayflies over substrate surfaces. Freshwat. Biol. 21: 253-260. Hartland- Rowe, T. 1953. Feeding mechanisms of an Ephemeropteran nymph. Nature 172: 1 109-

1110. Keltner, J. and W. P. McCafferty. 1986. Functional morphology of burrowing in the mayflies

Hexcigenia limbata and Pentagenia vittigera. Zool. J. Linn. Soc. 87: 139-162. Lehmkuhl, D. M. and N. H. Anderson. 1971. Contributions to the biology and taxonomy of the

Pamleptoplilebia of Oregon. Pan-Pac. Entomol. 47: 85-93. McCafferty, W. P. 1975. The burrowing mayflies (Ephemeroptera: Ephemeroidea) of the United

States. Trans. Am. Entomol. Soc. 101: 447-504. McCafferty, W. P. 1991a. Toward a phylogenetic classification of the Ephemeroptera (Insecta): a

commentary on systematics. Ann. Entomol. Soc. Am. 84: 343-360. McCafferty, W. P. 1991b. Comparison of Old and New World Acanthametropus (Ephemeroptera:

^canthametropodidae) and other psammophilous mayflies. Entomol. News 102: 205-214. McCa ferty, W. P. and Y. J. Bae. 1992. Filter-feeding habits of the larvae of Antlwpotamus (Ephe-

mtroptera: Potamanthidae). Ann. Limnol. 28: 27-34.

McCafferty, W. P. and G. F. Edmunds, Jr. 1973. Subgeneric classification of Ephemera (Ephe- meroptera: Ephemeridae). Pan-Pac. Entomol. 49: 300-307. McCafferty, W. P. and M. T. Gillies. 1979. The African Ephemeridae (Ephemeroptera). Aquat.

Insects 1: 169-178. Morgan, A. H. and M. C. Grierson. 1932. The functions of the gills in burrowing mayflies

(Hexagenia recurvata). Physiol. Zool. 5: 230-245.

76 ENTOMOLOGICAL NEWS

Morgan, A. H. and J. F. Wilder. 1936. The oxygen consumption of Hexagenia recurvata during

the winter and early spring. Physiol. Zool. 9:153-169.

Needham, J. G. 1927. A baetine mayfly nymph with tusked mandibles. Can. Entomol. 59: 44-47. Needham, J. G, J. R. Traver and Y.- C. Hsu. 1935. The biology of mayflies. Comstock, Ithaca,

NY. Peters, W. L. and I. C. Campbell. 1991. Ephemeroptera. pp. 279-293. In: I. D. Naumann et al.

[Eds.], The insects of Australia, 2nd edition. Melbourne Univ. Press, Melbourne. Saltier, W. 1967. Uber die Bebensweise, insbesondere das Bauverhalten, neotropischer

Eintagsfliegen-Larven (Ephemeroptera, Polymitarcidae). Beitr. Neotrop. Fauna 5: 89-110. Scott, D. C., L. Berner and A. Hirsch. 1959. The nymph of the mayfly genus Tortopus

(Ephemeroptera: Polymitarcidae). Ann. Entomol. Soc. Am. 52: 205-213. Soldii n, T. 1 978. Revision of the genus Palingenia in Europe (Ephemeroptera, Palingeniidae). Acta

Entomol. Bohem. 75: 272-284. Sweeney, B. W., J. K. Jackson and D. H. Funk. 1995. Semivoltinism, seasonal emergence, and

adult size variation in a tropical stream mayfly (Euthyplocia hecubd). J. N. Am. Benthol. Soc.

14: 131-146. Tolkamp, H. H. and J. C. Both. 1978. Organism-substrate relationship in a small Dutch lowland

stream. Preliminary results. Verh. Int. VerLimnol. 20: 1509-1515.

Vol. 107, No. 2, March & April, 1996 77

DENSITY AND DIVERSITY OF NONTARGET INSECTS KILLED BY SUBURBAN ELECTRIC INSECT TRAPS1

Timothy B. Frick, Douglas W. Tallamy2

ABSTRACT: Our survey of insects electrocuted during routine use of electric insect traps revealed only 31 biting flies, a minute proportion (0.22%) of the 13,789 total insects counted. In contrast, species from 12 orders and more than 104 nontarget insect families, including 1,868 predators and parasites (13.5%) and 6,670 nonbiting aquatic insects (48.4%) were destroyed. The heavy toll on nontarget insects and the near absence of biting flies in catches suggests that electric insect traps are worthless for biting fly reduction — and probably are counterproductive — to homeowners and other consumers.

Electric insect traps (e.g. , Zapper™, Bugwacker™ and Bug Blaster™; here- after, "zappers") use ultraviolet light to lure flying insects toward an electrified metal grid, where they are destroyed by the thousands on warm summer nights. Homeowners buy traps to rid their surroundings of annoying biting flies, and continuous snaps, crackles, and pops emanating from an active zapper seem to confirm their effectiveness. Traps are commonly used near aquatic habitats, waterfront areas, toll booths, campgrounds, industrial parks, restaurants, swim- ming pools, and suburban backyards. In suburban yards, traps are often run throughout the summer months, some only during the evening hours and some continually.

Although the target insects are primarily mosquitoes (Culicidae) and no- see-ums (Ceratopogonidae) that seek blood meals at the expense of homeowners, several factors make electric traps ineffective in reducing local mosquito popu- lations (Surgeoner & Kelson 1977, Nasci et al. 1983). Ultraviolet lamps that emit considerable amounts of visible light (as do the lamps sold in commercial electric traps) are less attractive to mosquitoes than lamps emitting only ultra- violet wavelengths (Ikeuchi 1967). Furthermore, many species of mosquitoes are not attracted to light traps at all (Pippin 1965, Miller et al. 1969) and those species that are are often not trapped in numbers proportionate to their popula- tion sizes (Bradley 1943, Huffaker & Back 1943, Fox 1958). But perhaps the most important reasons electric insect traps fail to reduce mosquito problems are that 1) carbon dioxide exhaled by homeowners is far more attractive to mosquitoes than are light traps (Headlee 1941, Huffaker & Back 1943, Nascit et al. 1983), and 2) mosquitoes that do move toward traps are rarely killed by electrocution devices (Service 1993).

1 Received August 18, 1995. Accepted September 21, 1995.

2 Department of Entomology and Applied Ecology, Delaware Agricultural Experiment Station, College of Agricultural Sciences, University of Delaware, Newark, Delaware 19717-1303.

ENT. NEWS 107(2): 77-82, March & April, 1996

78 ENTOMOLOGICAL NEWS

Electric insect traps are, however, effective at killing large numbers of non- target insects. Nasci etal. (1983) found that the average zapper in South Bend, Indiana killed more than 3000 insects per day, 96.7% of which were not female mosquitoes. Little beyond ordinal totals is known about the diversity and sea- sonal distribution of nontarget insects killed by zappers. As an initial step to- ward understanding the ecological consequences of indiscriminant removal by zappers of nontarget predators, parasitoids, and prey species from aquatic and terrestrial ecosystems, we quantified at the family level the numbers and kinds of insects killed over a season by homeowners' zappers in a suburban setting.

MATERIALS AND METHODS

We asked six homeowners with active bug zappers in suburban Newark, Delaware to participate in a summer-long study in 1994. All houses were within 3 km of a body of water. The house closest to water was about 65 meters from a large stream containing many stagnant eddies. Another house abutted a wooded area and was less than 1 km from a creek. The third house was about 1.5 km from the same creek but farther upstream. The fourth was in a wooded cul-de- sac through which ran a different creek; several permanent pools lay within 200 meters. The fifth house was situated in a residential development containing a stream and scattered wooded areas; a small pond about 30 meters long and 15 meters wide was less than a kilometer away. A small stream about 3 km distant was the nearest body of permanent water to the sixth house. Temporary pools, tree holes and water-filled containers were scattered throughout the study area. Thus, all traps were well within flight range of culicid and ceratopogonid breed- ing sites.

From June 20 to July 9, 1994, homeowners were asked to run the traps one night per week for at least two hours. Beginning on July 10, participants were asked to run their zappers one night per week every other week for the nine weeks ending August 27. A device constructed from a plastic dish 32 centime- ters in diameter was suspended beneath each trap to collect electrocuted in- sects. Each morning after the traps were run, we collected the samples from the six sites and stored them in a freezer until they could be counted and identified to family (except for Ephemeroptera,Psocoptera,Thysanoptera,and Trichoptera, which were identified only to order, and several families of moths, which were grouped as "Microlepidoptera").

RESULTS

We collected 31 samples from the traps over our ten-week study period in the summer of 1994. Nearly all electrocuted specimens, including the tiniest

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79

Cecidomyiidae, were well-preserved and easily identified. Twelve orders and more than 104 families were present in these samples and ranged in abundance from a single individual (several families) to more than 4,600 individuals (Chi- ronomidae; Table 1). Of the 13,789 insects killed by electric zappers in our study, only 3 1 individuals (0.22%) were biting flies (female Culicidae, Simuli- idae, and Ceratopogonidae). In contrast, insect predators, parasitoids, and nonbiting aquatic insects were abundant (Table 1). Present in our counts were representatives of 27 families of predators and nine families of parasitoids, to- taling 1,868 individuals (13.5%). Carabid beetles, staphylinid beetles, cicadel- lid leafhoppers, microlepidoptera, and braconid parasitoids were particularly common victims. Large numbers of aquatic insects, such as caddisflies (Tri- choptera) and midges (Chironomidae), were also destroyed; species from these families represented nearly half (48.4%) of sample totals.

Average numbers of insects per trap declined sharply over the season (Fig. 1), ranging from a mean of 1,304 insects per trap on June 20 to just 106 insects per trap on August 27. This probably reflects seasonal declines in the popula-

1600 1400

1200 1000 800 600 400 200

June

July

August

Fig. 1 . Seasonal pattern of insects killed at six electric insect traps in Newark, DE on six dates from June 20 to August 27, 1 994. Statistical interval = Standard Error. Pie charts depict the percentage of the total catch consisting of nontarget insects (black portion) and biting Hies (white portion) on each trapping date

80 ENTOMOLOGICAL NEWS

tions of species attracted to these traps. Although biting insects generally in- creased in proportion as the season progressed (from 0.26% of the total catch on June 20 to 1 .88% on August 20), they still comprised a minuscule portion of the total sample.

DISCUSSION

These data are straightforward: many thousands of nontarget insects repre- senting a rich taxonomic diversity were destroyed by these traps. Only a tiny fraction of trap victims were biting flies, the primary targets of electric zappers. Since we did not independently measure mosquito populations in our study sites we cannot definitively conclude that the zappers used in our study were ineffective mosquito killers. However, three types of circumstantial evidence suggest that this was indeed the case. First, it is highly unlikely that our low- land, wooded sites which were rich in aquatic breeding habitats, produced so few adult mosquitoes in the course of 9 weeks that 18 electrocuted females would represent adequate control of these flies. Second, the preponderance of aquatic insects in the samples suggests that our study traps were well within the flight range of biting flies that breed in water (culicids, ceratopogonids). Finally, our results are similar to those of Nasci et al. (1983) in which an inde- pendent measure of culicid populations confirmed the inability of zappers to attract mosquitoes that are present in suburban settings.

As we better understand the critical role insects play in the cohesion of most non-marine ecosystems, the sale and use of electric insect traps that so completely miss their advertised mark becomes increasingly irresponsible. It is insects and other invertebrates, not vertebrates, that are the "glue" of ecosys- tems; their elimination would inevitably lead to the rapid demise of those eco- systems and their members, including Homo sapiens (Wilson 1987). Even if targeted biting flies were effectively controlled by electric zappers, the result- ing destruction of thousands of parasitoids, predators, aquatic insects, and other members of the nocturnally active fauna would be difficult to justify.

Although we recognize its speculative shortcomings, a simple calculation underscores the degree to which electric zappers may affect nontarget insect populations. The seasonal mean catch per night (of at least 2 hr of trap time) as quantified by our study totaled 445 insects per trap. Approximately one million zappers are sold in the U.S. each year (Philadelphia Inquirer, 26 June 1995 p. 63). Electrocution devices are quite durable; the homeowners in our study had been operating their units for an average of 7 yrs prior to 1994. If, in any given year, 4 million traps are used for 40 nights during the summer, then 71,200,000,000 - - more than 71 billion nontarget insects — are needlessly destroyed in the U.S. each year by misinformed homeowners. If we substitute into our calculations the trap means obtained by Nasci et al. (1983) in Indiana (2163 insects during a 2 h trapping period; N = 10), this figure rises to nearly

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81

Table 1. Seasonal totals of biting flies (in bold), predators and parasitoids (italicized), plus other taxa killed by electric insect traps at six sites in Newark, DE.

No. % of

Order and Family Killed Total

Ephemeroptera 15 0.11

Dermaptera

Labiidae 2 0.02

Psocoptera 14 0.10

Hemiptera

Corixidae 10 0.07

Hebridae 2 0.02

Miridae 89 0.64

Nabidae 2 0.02

Lygaeidae 32 0.23

Rhopalidae 1 0.01

Cydnidae 14 0.10

Homoptera

Cicadidae 33 0.24

Cicadellidae 2421 17.56

Flatidae 8 0.05

Acanaloniidae 1 0.01

Psyllidae 41 0.30

Delphacidae 1 0.01

Cixiidae 1 0.01

Aphididae 25 0.18

Thysanoptera 16 0.12

Neuroptera

Corydalidae 1 0.01

Chrysopidae 8 0.05

Coleoptera

Carabidae 661 4.79

Dytiscidae 21 0.15

Hydrophilidae 83 0.60

Staphylinidae 306 2.22

Lucanidae 1 0.01

Scarabaeidae 219 1.58

Buprestidae 3 0.02

Elateridae 46 0.33

Lampyridae 12 0.09

Cantharidae 104 0.754

Dermestidae 11 0.08

Anobiidae 30 0.22

Cleridae 4 0.03

Nitidulidae 27 0.20

Coccinellidae 15 0. 1 1

Tenebrionidae 13 0.09

Mordellidae 10 0.07

Cerambycidae 11 0.08

Chrysomelidae 22 0.16

Curculionidae 7 0.05

Scolytidae 27 0.20

Diptera

Tipulidae 223 1.62

Psychodidae 11 0.08

Culicidae Cf 25, 9 18 0.31

Ceratopogonidae Cf 30, 9 12 0 30

Chironomidae 4612 33.45

Scatopsidae 13 0.09

Simuliidae 1 0.01

Bibionidae. 1 0.01

No. % of

Order and Family Killed Total

Mycetophilidae 34 0.25

Anisopodidae 13 0.09

Sciaridae 89 0.65

Dixidae 3 0.02

Cecidomyiidae 316 2.29

Stratiomyidae 5 0.04

Xylophagidae 1 0.01

Asilidae 1 0.01

Scenopinidae 1 0.01

Rhagionidae 2 0.02

Empididae 58 0.42

Dolichopodidae 70 0.51

Pipunciilidae 1 0.01

Phoridae 12 0.09

Platypezidae 4 0.03

Otitidae 2 0.02

Tephritidae 2 0.02

Sciomyzidae 1 0.01

Ephyd'ridae 8 0.05

Drosophilidae 7 0.05

Agromyzidae 14 0.10

Lonchaeidae 5 0.04

Lonchopteridae 8 0.05

Heleomyzidae 1 0.01

Sphaeroceridae 2 0.02

Anthomyiidae 28 0.20

Calliphoridae 17 0.12

Sarcophagidae 8 0.05

Tachinidae 16 0. 12

Trichoptera 1597 11.58

Lepidoptera

Microlepidoptera . . . 1121 8.13

Tortricidae 19 0.14

Pyralidae 316 2.29

Geometridae 35 0.25

Lasiocampidae 3 0.02

Arctiidae 11 0.08

Noctuidae 64 0.46

Notodontidae 2 0.02

Epipyropidae 5 0.04

Yponomeutidae 10 0.07

Hymenoptera

Braconidae 377 2.73

Ichneumonidae 77 0.56

Mymaridae 1 0.01

Perilampidae 1 0.01

Eulophidae 1 0.01

Encyrtidae 1 0.01

Pteromalidae 1 0.01

Torymidae 2 0.02

Eurytomidae 1 0.01

Chrysididae 3 0.02

Formicidae 84 0.6 1

Vespi 3 0.02

Halictidae. . .1 0.01

82 ENTOMOLOGICAL NEWS

350 billion nontarget insects. We suggest, therefore, that while there is no evi- dence that zappers control nuisance insects, their effects may be anything but benign. Studies investigating the effects of insect defaunation on local ecosys- tems in general and on specialized insectivores such as bats and nighthawks in particular are needed to evaluate the ecological costs of zappers and other hu- man activities destructive to insects. The results of our study indicate that ento- mologists, especially those active in extension, should be educating the public about the possible costs and lack of benefits from these gadgets.

ACKNOWLEDGMENTS

We gratefully acknowledge the Aftosmis, Fanny, Cherwaty, Walter, White, and Hawthorne families, and C. J. Murphy and A. Schleiniger for their cooperative participation in our study. R. R. Roth, H. Frick, R. G. Weber, and C. Tallamy made helpful comments on the manuscript. Published as Paper No. 1557 of the Delaware Agricultural Experiment Station; Contribution No. 678 of the Department of Entomology and Applied Ecology.

LITERATURE CITED

Bradley, G. H. 1943. Determination of densities of Anopheles quadrimaculatus on the wing. Proc.

New Jersey Mosq. Exterm. Assoc. 30:22-27. Fox, I. 1958. The mosquitoes of the international airport, Isla Verde, Puerto Rico, as shown by light

traps. Mosq. News 18:117-124. Headlee, T. J. 1941. New Jersey mosquito problems. Proc. New Jersey Mosq. Exterm. Assoc.

28:7-12. Huffaker, C. B., and R. C. Back. 1943. A study of methods of sampling mosquito populations. J.

Econ. Entomol. 36:561-569. Ikeuehi, M. 1967. Ecological studies on mosquitoes collected by light traps. Trop. Med. 9: 186-

200. Miller, T. A., R. G. Stryker, R. N. Wilkinson, and S. Esah. 1969. Notes on the use of CO2-baited

CDC miniature light traps for mosquito surveillance in Thailand. Mosq. News 29:688-689. Nasci, R. S., C. W. Harris, and C. K. Porter. 1983. Failure of an insect electrocuting device to

reduce mosquito biting. Mosq. News 43:180-44. Pippin, W. F. 1965. Notes on the operation of a light trap in central Luzon, Philippine Islands.

Mosq. News 25: 183-187. Service, M. W. 1993. Mosquito ecology: field sampling methods. 2nd edition. Elsevier Applied

Science, New York, New York. Surgeoner, G. A., and B. V. Helson. 1977. A field evaluation of electrocutors for mosquito control

in southern Ontario. Proc. Entomol. Soc. Ontario 108:53-58. Wilson, E. O. 1987. The little things that run the world (the importance and conservation of

invertebrates). Conservation Biology 1:344-346.

Vol. 107, No. 2, March & April, 1996 83

AN ATYPICAL LARVAL COLOR FORM OF BAETIS

INTERCALARIS (EPHEMEROPTERA: BAETIDAE)

FROM PENNSYLVANIA AND THE KIAMICHI RIVER

BASIN OF SOUTHEASTERN OKLAHOMA1

R.D. Waltz2, D.E. Baumgardner3-4, J.H. Kennedy4'5

ABSTRACT: An atypical larval color form of Baetis intercalaris was discovered and reared from the Kiamichi River basin of southeastern Oklahoma. Identical nymphs were also recently discovered in northeastern Pennsylvania. This atypical larval color form has been previously reported only from Wisconsin. Larvae of this color form are visually distinctive because they lack the pale triad of spots along the posterior margins of most abdominal tergites diagnostic of the typical color form. The atypical form is uniformly marked on each tergite with pale, anterior, paired incurved lines (parentheses like) on a gray or brown background, lacking the paler abdominal tergites and spots characteristic of typical B. intercalaris. No morphological characters in the adult stage or the larval stage were found to support establishment of a new species.

Independently conducted ecological studies of the macroinvertebrates in- habiting two disjunct river systems of North America resulted in the collection of a little reported form of Baetis intercalaris McDunnough. This larval color form is characterized by its lack of well developed and contrasting color pat- terns of the abdominal tergites when compared with the typical color form (see Morihara and McCafferty 1979). Bergman and Hilsenhoff (1978) first reported this unpatterned form in their studies of the Wisconsin Baetidae. The unpat- terned form is visually distinctive in field samples and is readily identified as unique due to the flat gray or brown, non-contrasting background color of the abdominal tergites (Fig. 1), typical "intercalaris" type of prothorax pattern (Morihara and McCafferty 1979), and medially banded cerci and terminal fila- ment. No other Baetis species in North America is similarly colored.

Larval specimens of the unpatterned form of B. intercalaris were collected and reared (by DEB) from the Kiamichi River basin of southeastern Oklahoma. Another series of identical specimens was collected and brought to the atten- tion of the senior author by James B. Munro, East Stroudsburg University, based on material that he collected in northeastern Pennsylvania. In each of the above cases, the unpatterned larval form was the only color form of this species found

1 Received October 14, 1995. Accepted November 6, 1995.

2 IDNR, Division of Entomology and Plant Pathology, 402 West Washington, Room W-290, Indianapolis, Indiana 46204.

3 Present Address: 9015 Rock Cliff, San Antonio, Texas 78230.

4 Department of Biological Sciences, University of North Texas, P.O. Box 5218, Denton, Texas 76203.

5 Present Address: Department of Biology, University of Texas Pan American, Edinburg, Texas 78539.

ENT. NEWS 107(2): 83-87, March & April. 1996

84 ENTOMOLOGICAL NEWS

at the site. Typical color forms of B. intercalaris were not present in sites where collections were made of the unpatterned form.

MATERIAL EXAMINED

Material which formed the basis for this report includes the following lar- val, adult, and reared adult specimens:

OKLAHOMA: Pushmataha Co., Kiamichi R. at Hwy 2, 16.3. mi N Hwy 2-3 jet, D.E. Baumgardner, 16-IX-1993, 2L, and 14-X-1993, 2 reared male adults, 1 reared female adult, 7L. OK: Le Flore Co., Kiamichi R. at Hwy 259, approx. 0.5 mi S Hwy 63-259 jet, 18-VII-1993, D.E. Baumgardner, 2L. OK: Le Flore Co., Pigeon Crk at Hwy 63, approx. 5.5 mi W Oklahoma-Arkan- sas border, 19-VI- 1993, D.E. Baumgardner, 1 male adult. OK: Pushmataha Co., Dry Crk at un- named low water crossing, approx. 2.5 mi ETuskahoma, 17-VII-1993, D.E. Baumgardner, 1L.

PENNSYLVANIA: Pike County, Blooming Grove Creek, 6, 27-VII 1993; 10, 24-VIII-1993; 9-IX-1993, and 4-X-1993, James B. Munro.

Representative vouchers have been deposited in the Purdue Entomological Research Collection, West Lafayette, Indiana, and University of North Texas, Denton, Texas.

IDENTIFICATION

Larvae of the unpatterned form will reach an impasse in the key couplet separating Baetis intercalaris from B. flavistriga McDunnough in Morihara and McCafferty (1979: couplet 19) because the tergal pale spots are not present. To accommodate identification of the unpatterned form, couplet 19 of the key may be modified to read:

19. Darker, well-marked abdominal tergites with two large submedian pale areas, often kidney shaped B. flavistriga

19'. Darker, well-marked abdominal tergites with 3 posterior round pale areas, middle spot often smaller than laterals or abdominal tergites uniformly gray or brown with pale parentheses-like marks at middle, anterior margin of each tergite B. intercalaris

Confirmation of tentative larval identifications using this modified couplet should continue to be accomplished by using the expanded diagnosis under the species discussion of B. intercalaris in Morihara and McCafferty (1979). In some specimens, the slide mounted larval exuviae of the unpatterned form showed indication of pale tergal areas on the anterior tergites when examined with indirect substage lighting.

The adult of the reared, atypical larva keys readily to B. intercalaris in the most recent keys to the Baetis species adults (Traver 1935) based on the elon- gated marginal intercalaries of the first interspace in the forewing. However, adults of the reared atypical specimens possessed a dark-brown thorax, rather

Vol. 107, No. 2, March & April, 1996

85

Figure 1. Baetis intercalaris (unpatterned form). Dorsal habitus (photograph).

86 ENTOMOLOGICAL NEWS

than the black thorax of typical B. intercalaris. Such color differences in the adult stage have been regarded as within the observed limits of intraspecific variation in closely allied species, e.g., B. flavistriga (see Morihara and McCafferty 1979 and Traver 1935) and in Baetis dubius (Walsh) (Waltz, per- sonal observation). Further comparisons of the adult male reared from the un- patterned larval form with adult males reared from typical B. intercalaris larvae showed no discernible morphological differences.

BIOLOGY AND DISCUSSION

Baetis intercalaris, widely distributed in the Kiamichi River drainage, was collected from third through fifth order streams in the upper, middle, and lower reaches of the drainage. Larvae were collected from gravel/pebble substrate in riffles. Other studies have reported similar habitats for this species (Bergman and Hilsenhoff 1978; Berner and Pescador 1988).

Baetis intercalaris may have two generations per year in the Kiamichi River drainage, consisting of a spring and a fall generation. Immature larvae were first collected in June 1993, with late instar and emerging larvae collected in October, indicating the fall generation. Although no larvae were collected be- fore June, a single adult was collected in June 1993, suggesting the occurrence of a spring generation. In the northern regions of its range, B. intercalaris has been reported variously as univoltine (Bergman and Hilsenhoff 1978; Harper and Harper 1984), or bivoltine (McDunnough 1921, 1923; Ide 1935). Emer- gence of B. intercalaris occurs throughout the year in the southern regions of its range (Berner and Pescador 1988), and often has no cohort synchronization (Jacobi and Benke 1991).

The cause of the atypical color variation is unclear at this time. The atypical color form could represent a cryptic species. A second, and more probable cause, is that this atypical color form may be a result of some, as yet not identified, environmental factor causing the differences in color. Not only are there no obvious morphological differences in the typical versus the atypical forms, but the presence of patterning common to the typical form, that is vaguely discern- ible in at least some larvae of the atypical form, leads us to seek an environmen- tal cause for the atypical coloration. All of the unpatterned form larvae reported herein were collected in the mid to late summer, or the second generation cycle. No earlier, or spring generation, collections of the unpatterned form are known to us. Additional studies, including rearings of both typical and atypical color forms from throughout the range of this species, and life history studies, will be required to better understand the source of this atypical coloration.

ACKNOWLEDGMENTS

We thank James B. Munro and Bruce Haase, East Stroudsburg University, PA, for making their material of Baetis intercalaris (unpatterned form) available for study.

Vol. 107, No. 2, March & April, 1996 87

LITERATURE CITED

Bergman, E.A. and W.L. Hilsenhoff. 1978. Baetis (Ephemeroptera: Baetidae) of Wisconsin. Gr.

Lakes Entomol. 11: 125-135. Berner, L. and M.L. Pescador. 1988. The Mayflies of Florida, Revised Edition. University Presses

of Florida. 415 pp. Harper, P.P. and F. Harper. 1984. Phenology and distribution of mayflies in a southern Ontario

lowland stream, pp. 243-25 1 . In:. V. Landa, el al. (eds.), Proc. Fourth Intntl. Conf. Ephemeroptera.

Czechoslovakia. Ide, F.P. 1935. The effect of temperature on the distribution of the mayfly fauna of a stream. Univ.

Toronto Stud., Biol Ser. 39, Pub. Ontario Fish Res. Lab. 50: 9-76. Jacobi, D.I. and A.C. Benke. 1991. Life histories and abundance patterns of snag-dwelling mayflies

in a blackwater Coastal Plain River. J. N. Am. Benth. Soc. 10: 372-387.

McDunnough,J. 1921. Two new Canadian Mayflies (Ephemeridae). Can . Entomol. 53: 117- 120. McDunnough, J. 1923. New Canadian Ephemeridae with notes. Can. Entomol. 55: 39-50. Morihara, O.K. and W.P. McCafferty. 1 979. The Baetis larvae of North America (Ephemeroptera:

Baetidae). Trans. Am. Entomol. Soc. 105: 139-221. Traver, J.R. 1935. Part II, Systematic, pp. 239-739. In:. J.G. Needham, J.R. Traver, Y.C. Hsu (eds.),

The biology of mayflies with a systematic account of North American species. Comstock Publ.

Co., Ithaca, NY.

88 ENTOMOLOGICAL NEWS

A NEW PERUVIAN MUSAPSOCID GENUS AND SPECIES (PSOCOPTERA: MUSAPSOCIDAE)1

Alfonso Neri Garcia Aldrete^, Edward L. Mockford^

ABSTRACT: Musapsocoides nadleri, n. gen., n. sp., is described from a pair of specimens collected in Tarma, Peru. It is the sister group to Musapsocus, the only other known genus of the family, from which it differs in having three-segmented tarsi, male clunium without papillar or spinous fields, third valvula bilobed apically, subgenital plate with only a few stout setae located medially on distal margin, and in shape and structure of the male epiproct and phallosome and the female spermathecal duct. The discovery of this genus will probably have a considerable impact on the interpretation of the phylogeny of the electrentomoid Psocoptera.

The family Musapsocidae has hitherto included only the genus Musapsocus Mockford (1967), which stands well apart from other electrentomoid genera. The genus currently includes eight described species ranging from the tropical lowlands of Mexico south to central Brazil and central Peru (Mockford 1967, 1 99 1 ). This paper describes a sister taxon to Musapsocus collected in west-cen- tral Peru. The pair of specimens on which the study was based were mounted in pa