PROC. ENTOMOL. SOC. WASH. 92(4), 1990, pp. 746-756

A REVISION OF THE SHORE- GENUS DIPHUIA CRESSON (DIPTERA: EPHYDRIDAE)

Wayne N. Mathis

Department of Entomology, NHB 169, Smithsonian Institution, Washington, D.C. 20560.

Abstract. —Diphuia Cresson, a New World genus of shore , is revised and found to be close phylogenetically (the sister group) to the lineage giving rise to Allot richoma Becker, including Pseudohecamede Hendel. Although four species (D. anomala Cresson, D. nasalis Wirth, D. nitida Sturtevant and Wheeler, and D. zatwarnickii. new species (Jamaica) are recognized, the second and third are very similar and may prove to be conspecific when adequate material of D. nitida is available. Characters of the male postabdomen and terminalia are described and illustrated.

Key Words: Ephydridae, shore flies, Diphuia. revision, systematics

While conducting field work on several crotomentum, and having a distinctively cays within the Stann Creek District of Be- marked face that is black with silvery white, lize, I found a tiny, black-colored shore fly microtomentose lines. The facial markings that is associated with mangrove peat. The of microtomentum are similar to specimens peat, which is exposed at low tide, is shaded of nitida Cresson (tribe Disco- during most of the day beneath the dense cerinini) and several genera of the tribe canopy of well-developed fringe red man- Gymnomyzini. The superficial resemblance grove (Rhizophora mangle L.). The speci- of this genus to discocerines or gymnomy- mens did not occur on peat that is the sub- zines prompted Cresson to formulate the strate for scrub or dwarf red mangrove and generic name Diphuia. which is a Latin where little or no shade is provided. Deter- transliteration of Greek words meaning mining the identity of this species, which is double nature. Although similar to genera less than two mm in length, has led to this in other tribes, the genus is related most revision of Diphuia Cresson, the genus to closely to Allotrichoma. as Cresson con- which the species has been assigned. In ad- cluded in the original description, and the dition to determining the identity of the similarities noted are apparently the result specimens from Belize, the other specific of convergences. purposes of this revision are to provide the When Cresson ( 1 944) originally proposed first illustrations of the male terminalia and Diphuia he included only the type species, to determine the phylogenetic position of D. anomala Cresson, which was described Diphuia, which Cresson (1944) suggested in the same paper. Two years later, Cresson was related to Allotrichoma Becker in the again treated Diphuia and its type species tribe Atissini. in his synopsis of Neotropical Psilopinae (=

Shore flies of the genus Diphuia are anom- ). The genus then remained alies among atissines in being mostly black, unstudied for nearly a decade, which is not lacking dense vestiture of gray to brown mi- surprising in view of their diminutive size, VOLUME 92. NUMBER 4 747 restricted distribution, and rarity in collec- cumulated several specimens of what ap- tions. Sturtevant and Wheeler (1954) wrote peared to be the same tiny fly. His collec- the concluding part for Cresson's synopses tions from Jamaica and Dominica are of Nearctic shore flies, following the latter's especially noteworthy in that regard. I also death, and described D. nitida from a single examined collections of the Academy of specimen that was collected near New York Natural Sciences of Philadelphia (ANSP), City. Two years afterwards, Wirth (1956) the American Museum of Natural History reviewed the shore flies of the Bahamas and (AMNH), and the University of Texas described a third species, D. nasalis. Aside (UTA). from catalogs of the Nearctic and Neotrop- Diphuia Cresson ical Regions (Wirth 1965, 1968, respective- ly), no further work has been published on Diphuia Cresson, 1944: 4. Type species: Di-

Diphuia. Nothing is known of the immature phuia anomala Cresson, 1 944, by original stages, no key is available, and the structures designation; 1946: 138, 140 [note, key].— of the male terminalia have not been in- Sturtevant and Wheeler, 1954: 248 vestigated, described, or illustrated. [notes]. — Wirth, 1956: 4 [discussion of Methods.— The terminology and meth- species]; 1968: 5 [Neotropical catalog]. ods used in this study were explained pre- Diagnosis. — Mostly black, subshiny to viously (Mathis 1986a, b). Because of the shiny, microtomentum usually sparse; smaU small size of specimens, study and illustra- shore flies, length 1.35 to 1.80 mm. tion of the male terminalia required the use Head: Wider than high; face width-to- of a compound microscope. To better as- head width ratio 0.28; frons black, mostly sure eflfective communication about struc- unicolorous, lacking distinctively colored tures of the male terminalia, I have adopted ocellar triangle; frons wider than long, fron- the terminology of other workers in Ephyd- tal length-to-width ratio 0.58; frontal ves- ridae (see references in Mathis 1986b). Us- titure variable; ocellar seta well developed, age of these terms, however, should not be inserted slightly in front of alignment of an- taken as an endorsement of them from a terior ocellus and at about the same distance theoretical or morphological view over al- apart as between posterior ocelli; pseudo- ternatives that have been proposed (Grif- postocellar setae usually well developed, fiths 1972, McAlpine 1981). Rather, I am length subequal to ocellar setae, proclinate, deferring to tradition until the morpholog- slightly divergent; 1 reclinate and 1 procli- ical issues are better resolved. Two venational ratios are used common- nate fronto-orbital seta present, reclinate seta slightly anteromediad of proclinate ly in the descriptions and are defined here inserted for the convenience of the user (ratios are seta; both inner and outer vertical setae averages of three specimens). present; ocelli arranged to form isosceles tri- distance posterior ocelli 1. Costal vein ratio: the straight line dis- angle, with between tance between the apices of R2+3 and R4+5/ larger than between anterior ocellus and ei- distance between the apices of R, and R2+3. ther posterior ocellus. Antenna exerted; 2. M vein ratio: the straight line distance pedicel with well-developed, proclinate, along M between crossveins (dm-cu and dorsal seta; aristal length subequal to an- r-m)/distance apicad of crossvein dm-cu. tennal length and bearing 4-5 dorsal rays, Most of the specimens used in this study, with basal 3 rays longer than apical 1-2, the a total of 225, are housed in the National latter subequal. Eye apparently bare of mi- Museum of Natural History (USNM), crosetulae (using a stereomicroscope). Face Smithsonian Institution. Prior to my tenure black in both sexes and with silvery white, at the Smithsonian, W. W. Wirth had ac- microtomentose antennal grooves and with ,

748 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON

2 lines, sometimes irregular, paralleling par- sclerotized, elongate, not normally visible afacials, these and similarly invested and from a dorsal view, usually retracted within colored ventral margin (microtomentum 4th segment; 5th tergum and sternum of sometimes interrupted at middle) form a male united anteriorly to form a complete facial triangle that has a small microtomen- annulus. Male terminalia as follows: cercus tose area below facial prominence; face not rod shaped, bearing 2-3 conspicuously lon- carinate between antennal bases but slight- ger setae at ventral margin; surstylus well ly, conically protrudent at middle (best seen developed, well sclerotized, and conspicu- in lateral view); ventral facial margin shal- ous, length as long as cercus. lowly emarginate; face bearing 2 facial setae, Distribution. — New World. Temperate to the dorsal seta very slightly larger, both in- tropical zones, in North America along the serted near parafacials; parafacials densely east coast (New York south to Florida) and microtomentose, silvery white; clypeus very the Caribbean to Colombia and Eucador in sparsely microtomentose, black; palpus South America. blackish brown to black; mouthparts not Phylogenetic relationships.— £)/;7/;iHecamede Haliday) microtomentum variable with species, al- within the tribe Atissini that is character- though generally sparse; pleural areas lack- ized by having very sparse or lacking mi- ing stripes of distinctly colored microto- crosetulae on the compound eyes; a coni- mentum. Chaetotaxy with mesonotal setae cally prominent face (degree of development poorly developed except for those at pos- varies) that is emarginate ventrally and with terior margin; mesonotal setulae numerous the clypeus exposed in the emargination; and not arranged in well-defined setal tracks; oral opening and clypeus narrow; area sur- prescutellar acrostichal setae much larger rounding crossvein dm-cu not infuscate; the than other acrostichal setulae and more apex of the wing broadly rounded, not widely set apart; only 1 dorsocentral seta, pointed at the apex of vein R4 + 5; fifth ter- inserted posteriad; intra-alar setulae irreg- gum of male retracted within the enlarged ularly seriated; presutural seta well devel- fourth, usually not visible; and cerci with oped, length subequal to notopleural setae; elongate setulae at ventral margin. Diphuia 2 scutellar setae and scutellar disc with appears to be the sister group to the lineage sparse, scattered setulae; postpronotal seta giving rise to taxa closely related to Allotri-

1; postalar seta 1; notopleural setae 2, in- choma sensu lato, including Pseudohe- sertion of posterior seta elevated dorsally camede. This relationship is evidenced by above anterior one; anepistemal setae 2, in- the characters noted previously, especially serted along posterior margin; katepistemal the retracted fifth tergum of the male, which seta well developed, conspicuous. \Mng: is moderately elongate, almost tubular. Al- membrane mostly hyaline to very slightly though related and similar to this group, milky white; veins behind costa pale, usu- Diphuia may be distinguished as follows ally yellowish to yellowish brown; vein R2+ (characters indicated by an asterisk are aut- extended well beyond level ofcrossvein dm- apomorphies that corroborate the monophy- cu, 2nd costal section at least 1 '/j times lon- ly of Diphuia): *coloration very dark, usu- ger than 3rd section; alular marginal setulae ally black; *microtomentum of head and short, less than '/2 alular height. Legs: fem- thorax generally sparse, giving a subshiny ora black; tibiae dark basally, concolorous to faintly dull appearance; facial coloration with femora, apices yellowish. of male and females similar, lacking sexual Abdomen: Fifth segment of male well dimorphism; face, although slightly pro- VOLUME 92. NUMBER 4 749 trudent medially (best seen in profile), not 2. Mesonotum thinly invested with microtomen- tum. subshiny; anepistemum with anteroven- acutely pointed in lateral view; *face with tral 'A-'/; bare, shiny black, otherwise with thin silvery microtomentose markings, antennal

investment of whitish gray microtomentum , grooves, 2 vertical lines, ventral margin, an D. nasalis Wirth area below the facial prominence, and par- - Mesonotum moderately densely microtomen- afacials; presutural and prescutellar setae tose. golden brown; anepistemum almost en- tirely invested with whitish gray microtomen- well developed; *pleural region lacking a tum 3 stripe or stripes; 5th segment of male well 3. Surstyli long and narrow, length subequal to sclerotized its moderately and tergum en- that of cercus (Fig. 3); gonite with pointed pos- longate; *5th tergum and sternum of male teroventrally; aedeagus only moderately curved united anteriorly to form a complete an- apically D anomala Cresson - Sturstylimoderately short and robust (Fig. 18), nulus; and male genitalia with distinct, well- length shorter than cercus; gonite with poster- sclerotized, elongate surstyli. The place- oventral portion broadly bifurcate; aedeagus ment of Diphuia as the sister group to the more curved apically, point onented anteriorly lineage of Allotrichoma sensu lato follows C. zatwarmckn. new species Cresson's original assessment. The evi- dence supporting this relationship is not Diphuia anomala Cresson strong, however, and Diphuia could be re- Figs. 1-7 lated to Hecamede. Diphuia anomala Cresson, 1944: 4; 1946: Two species groups are evident within Di- 138 [review]. -Wirth, 1968: 5 [Neotrop- phuia, each comprising two species: D. ical catalog]. anomala Cresson and D. zatwarnickii. a new species that is described below; and D. ni- Description.— Small shore flies, length tida and D. nasalis. For species in the former 1.60 to 1.80 mm. group, I have found that characters of the Head: Frons moderately invested with male terminalia only are adequate to dis- brownish microtomentum, microtomen- tinguish between the species. In the second tum sparse or lacking on 2 small areas la- group, the degree of microtomentum on the terad of posterior ocelli and 2 spots along frons may be a distinguishing character, al- the anterior margin. though that character is questionable (see Thorax: Mesonotum densely invested "Remarks" under D. nitida). with brownish to golden brown microto- Discussion.— Two shore-fly species (Dis- mentum, especially medially, along poste- cocerina quadripectinata (Becker) and Al- rior portion of scutum and scutellum; an- lotrichoma argentipraetextum Lamb) that epistemum with fine investment of whitish are now or perhaps should be assigned to microtomentum. Wing with costal vein ra- Allotrichoma and related genera and that are tio 0.50; M vein ratio 0.41. dark colored are not closely related to Di- Abdomen: 5th tergum (Figs. 1, 2) almost phuia (Zatwamicki, in litt.). as high as long, anterior margin in dorsal Nothing is known about the immature view with deep, broadly V-shaped emargi- stages or natural history ofany of the species nation (Fig. 2), posterior margin with sparse included in Diphuia. setae; 5th sternum clearly divided into 2 broad stemites that are connected only an- Key to Species of Diphuia teroventrally (Fig. 1 ). Male terminalia (Figs.

1 . Mesofrons bare of microtomentum, shmy (New 3-7) as follows: epandrium bulbous, shiny, York) D. mtida Sturtevant and Wheeler in lateral view almost as wide as high (Fig. - Mesofrons mostly densely microtomentose, at 3); surstylus long, narrow, parallel sided, most with small shiny area immediately before anterior ocellus (southeastern USA and Neo- width and length subequal to that of cercus, tropics) 2 apex angulate, pointed anteriorly, and bear- 750 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON

ing a few setulae (Fig. 3); gonite broad bas- alia (see "Remarks" under D. zatwarnickii ally, with posteriorly extended process and couplet 3 of the key). From D. nasalis sheathing aedeagus, posterior apex of gonite and D. nitida it may be distinguished by the curved anteroventrally (Figs. 4, 5); aedeagal following characters: frons and mesonotum apodeme triangular in lateral view (Figs. 5, invested moderately densely with brownish

7), narrowly produced dorsally; aedeagus in to golden brown microtomentum; anepi- lateral view broad, thumblike, produced stemum invested with fine, grayish to whit- posteroventrad to a ventral point, in dorsal ish microtomentum, anteroventral portion view becoming wider apically, apex broadly not bare, shiny; second costal section long, rounded (Figs. 5,7); hypandrium in ventral costal vein ratio 0.50; and several characters view longer than wide, anterior margin with of the male terminalia (see description and a small, anterior process (Figs. 5, 6). figures). Type material.— The holotype male is nasalis Wirth labeled "Monte Lirio[,] PANAMA[,] Diphuia Figs. 8-15 RCShannon[,] IV. 6. 23 [6 Apr 1923J/3/ TYPE DIPHUIA ANOMALA 6 E.T. Cres- Diphuia nasalis Wirth, 1956: 3; 1968: 5 son, Jr. [red, species name and 6 handwrit- [Neotropical catalog]. ten]; TypeNo 70450 USNM [red, number Description. — Small shore flies, length handwritten]." The holotype is point 1.35 to 1.75 mm. mounted, is in good condition (the right first Head: Frons sparsely invested with fine flagellomere is missing), and is deposited in brownish microtomentum, microtomen- the USNM. The allotype and several para- tum becoming sparser or lacking on 2 small types are also deposited in the USNM. areas laterad of posterior ocelli, 2 spots along Other specimens examined. — COLOM- the anterior margin, and sometimes a small BIA. Rio Raposo (light trap), Jan 1964, V. spot in front of the anterior ocellus. H. Lee (1

phuia. It is very similar externally to D. zat- terior angles produced into pointed pro- warnickii and can be distinguished only by cesses, posteroventral process sinuate (Figs. reference to structures of the male termin- 11,1 2); aedeagal apodeme rounded anter- VOLUME 92, NUMBER 4 751

Figs. 1-7. Diphuia anomala. 1, 5th tergum and sternum, lateral view. 2. 5th tergum. dorsal view. 3, Male terminalia (epandnum, cercus, surstyli), lateral view. 4, Gonite. lateral view. 5, Internal male terminalia (gonite, hypandrium, aedeagal apodeme, aedeagus). lateral view. 6, Hypandrium and aedeagal apodeme, ventral view. 7, Aedeagus and aedeagal apodeme. lateral view. Scale bar = 0.1 mm. oventrally (Figs. 12, 13); aedeagus acutely good condition (tip of right wing folded back pointed apically, in dorsal or ventral view on itself), and is deposited in the AMNH. bifurcate apically {Figs. 12-14); hypan- Although the holotype was listed as a male drium in ventral view wider than long, an- (Wirth 1956: 4) and the specimen is so terior margin shallowly arched anteriorly marked, it is a female. (Figs. 12, 14, 15). Other specimens examined. — 5.-^//.-l- Type material. — The holotype female is MAS. Crooked Island, Landrail Point, 5 Mar labeled "Long Island[,] Deadman's Cay[,] 1953, E. B. Hayden, L. Giovannoli (1 2;

March 11, 1953/Van Voast-A.M.N.H. AMNH); Exuma Cays, Staniard Bay, 1 3 Jan

Bahama Isls. Exped Coll. E. B. Hayden/6/ 1953, E. B. Hayden (1 9; AMNH); Long

3HOLOTYPE Diphuia nasalis W. W. Wirth Island, Deadman's Cay, 1 1 Mar 1953, E. B.

[red, gender and species name handwrit- Hayden (2 $\ AMNH, USNM). BELIZE. ten]." The holotype is point mounted, is in Stann Creek District: Bread and Butter Cay, 752 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON

Figs. 8-15. Diphuia nasalis. 8. 5th tergum and sternum, lateral view. 9, 5th tergum. dorsal view. 10, Male tcrminalia (epandrium, cercus. surstyli). lateral view. 11, Gonite, lateral view. 12, Internal male terminalia (gonite, hypandnum. acdeagal apodeme, aedeagus), lateral view. 13, Aedeagus and aedeagal apodeme, lateral view. 14, Hypandnum. aedeagal apodeme, and aedeagus, ventral view. 15, Hypandnum, lateral view. Scale bar = 0.1 mm.

25 Mar 1988, W. N. Mathis (5 <5, 1 2; Cays (West Bay), 22 Mar 1 988, W. N. Math-

USNM); Glover's Reef (Long Cay, Middle is (1 <5, 1 2; USNM); Wee Wee Cay, 24-25

Cay, Northeast Cay, Southwest Cay), 26- Mar 1988, 21 Jul 1989, W. N. Mathis (5 $;

28 Jul 1989, W. N. Mathis (29

USNM); Man ofWarCay, 8-15 Nov 1987, (1 <5; USNM). BERMUDA. Hamilton Par-

W. N. & D. Mathis (7 3, 4 2; USNM); Twin ish. Shelly Bay, 20 Nov 1 987, D. J. Hilbum, 1

VOLUME 92, NUMBER 4 753

Figs. 16-22. Diphuia zatwarnickii. 16. 5th tcrgum and sternum, lateral view. 17, 5th tergum, dorsal view. 18, Male terminalia (epandnum, cercus, surstyli), lateral view. 19, Internal male terminalia (gonite, hypandrium, aedeagal apodeme, aedeagus), lateral view. 20, Gonite, lateral view. 21, Aedeagus and aedeagal apodeme, lateral view. 22, Hypandnum, ventral view. Scale bar = 0.1 mm.

N. E. Woodley (2 9; USNM). JAMAICA. Runaway Bay (bay shore), 16-28 Feb 1969,

Falmouth (bay shore), 1 Mar 1969, W. W. W. W. Wirth (3 <5; USNM). UNITED

Wirth (1 <5; USNM); Milk River Bath (man- STATES. Florida. Monroe Co., Bahia Hon- groves), 1 1 Mar 1970, T. Farr, W. W. Wirth da Key (seashore), 11 Apr 1970, W. W.

1 (5 6, 1 2; USNM); Negril Beach (rocky shore), Wirth (4

12 Mar 1970, W. W. Wirth (1 <5; USNM); Apr-30 Dec 1954, 1970, H. V. Weems (1 754 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON

29 Dec 1953, H. V. Weems ( 1

1 1 Aug 1975, J. C. Dukes (1 9; USNM). setae are missing and the left side of the Distribution. — Bahamas, Belize, Bermu- body and wings are covered partially with da, Jamaica, and USA (Florida, North Ca- glue), and is deposited in the ANSP (6695). rolina). Sturtevant and Wheeler stated that this

Natural history. — The vast majority of specimen is a male, but is clearly a female. specimens from the Belizean cays were col- Distribution. — USA. New York: Long Is- lected by sweeping just above mangrove peat land, Douglaston (just within the city limits that is well shaded most of the day. A few of New York City). specimens, apparently feeding, were col- Remarks.— This species is very similar lected on flowers. The association with to, and may be conspecific with, D. nasalis. mangrove peat must be opportunistic, as Resolution of this question will depend on the species occurs in areas where mangrove collection and study of additional material, does not now exist. especially males, from the type locality or Remarks.— This species is distinguished a locality nearby. At present, the only known from congeners, especially D. anomala and specimen of this "species" is the female ho-

D. zatwarnickii, by the sparsely microto- lotype, which, as noted earlier, is in poor mentose mesofrons (although not shiny as condition, making it impossible to ascertain in D. nilida); the subshiny mesonotum that its identity with certainty. I recognize the is very thinly invested with fine microto- holotype as being diflferent and possibly rep- mentum; the shiny anteroventral one-third resenting a separate species mostly because to one-half of the anepistemum; and several the few external features that are discem- characters of the male terminalia (see de- able, especially those of the head, are not scription and figures). within the variation among specimens of/).

nasalis that I have studied. The shinier frons Diphuia nitida Sturtevant and Wheeler of the holotype appears to be unique. Fur- Diphuia nitida Sturtevant and Wheeler, thermore, the distance between New York, 1954: 248.-Wirth, 1965: 737 [Nearctic which is the type locality of this species, and

catalog]. the nearest locality where D. nasalis is known

is several Description.— Small shore flies, length to occur (North Carolina) hun- 1.60 mm. dreds of miles. As these populations are Head: Frons, except for fronto-orbits, somewhat disjunct and are apparently dif- bare, shiny, especially mesofrons and fron- ferent, I am provisionally recognizing them tal triangle: fronto-orbits invested with as representing separate species. If the pop- brown microtomentum; frontal triangle ulations prove to be conspecific, D. nitida chestnut brown, mesofrons otherwise black. is the senior synonym. Thorax: Mesonotum sparsely microto- Diphuia zatwarnickii. New Species mentose, subshiny to shiny, black; anepi- Figs. 16-22 stemum mostly shiny, posterodorsal angle with some grayish to whitish microtomen- Description. — Small shore flies, length tum. 1.40 to 1.90 mm. Type material. —The holotype 9 is labeled Head: Frons moderately invested with "Dougl[t]s[t]on[,] L[ong]. I[sland]., N[ew]. brownish microtomentum, microtomen- Y[ork].[,] Au[gust]. 17, [19]52/HOLO- tum sparse or lacking on 2 small areas la- VOLUME 92, NUMBER 4 755

terad of posterior ocelli and 2 spots along Bueno, 21 Feb 1969, W. W. Wirth (1 S; the anterior margin. USNM); Savanna La Mar, 13 Mar 1970,

Thorax: Mesonotum densely invested W. W. Wirth (2 6; USNM). The holotype is with brownish to golden brown microto- double mounted (minute nadel in polyporus mentum, especially medially, along poste- block), is in excellent condition, and is de- rior portion of scutum and scutellum; an- posited in the Smithsonian Institution epistemum with fine investment of whitish (USNM). microtomentum. Wing with costal vein ra- Distribution. — West Indies: Dominica tio 0.52; M vein ratio 0.42. and Jamaica. /lMow?«; 5th tergum (Figs. 16, 17) about Etymology.— This species is named for as high as long, anterior margin in dorsal Tadeusz Zatwamicki, who first brought this view with deep, broadly V-shaped emargi- species to my attention and who has con- nation (Fig. 1 7), posterior margin with sparse tributed significantly to the study of shore setae; 5th sternum clearly divided into 2 flies. broad stemites that are connected only an- Remarks.— This species is distinguished teroventrally (Fig. 16). Male terminalia from D. nasalis and D. nitida by the sparsely (Figs. 18-22) as follows: epandrium bul- microtomentose mesofrons; the subshiny bous, shiny, in lateral view almost as wide mesonotum that is very thinly invested with as high (Fig. 1 8); cercus cylindrical; sursty- fine microtomentum; the shiny anteroven- lus moderately long and narrow, parallel tral one-third to one-half of the anepister- sided, width subequal to that of cercus but num; and several characters of the male ter- length shorter, apex angulate, pointed an- minalia. This species is distinguished from teriorly, and bearing a few setulae (Fig. 18); D. anomala by characters of the male ter- gonite broad basally, with posteriorly ex- minalia: especially the shorter, more robust tended process sheathing aedeagus, poste- surstyli; the gonite that is broadly bifurcate rior apex of gonite bifurcate (Figs. 19, 20); posteroventrally; and the more apically aedeagal apodeme triangular in lateral view curved aedeagus (see description and fig- (Figs. 19, 21), narrowly produced dorsally; ures). aedeagus in lateral view broad, thumblike, ACKNOWLEtX3MENTS curved posteroventrad to an anteroventral point, in dorsal view becoming wider api- I am grateful for the assistance in the field cally, apex broadly rounded (Figs. 19,21 ); from Candy Feller, Holly Williams, and hypandrium in ventral view longer than Dianne Mathis. For the opportunity to ex- wide, anterior margin with a small, anterior amine specimens housed in their collec- process (Fig. 22). tions, I thank David Grimaldi and Julian Type material.— The holotype male is la- Stark (AMNH) and Donald Azuma (ANSP). beled "JAMAICA 5mi.E.Negril 13March For critically reviewing a draft of this paper,

1970 W. W. Wirth fresh marsh." The al- I thank Allen Norrbom, Norman Woodley, lotype female and three other paratypes (2 Willis Wirth, and Tadeusz Zatwamicki. The

(3, 1 9; USNM) bear the same label data as illustrations were skillfully inked by Elaine the holotype. Other paratypes are from: R. S. Hodges. DOMINICA. Cabrit Swamp, 22-25 Mar Funding for this research project, espe-

1965, W. W. Wirth (6 3, 2 2; USNM); cially the field work in Belize, was provided Woodford Hill, 27 Feb 1965, W. W. Wirth by the Caribbean Coral Reef Ecosystems

(2 3; USNM). JAMAICA. Kingston, Fresh (CCRE), Smithsonian Institution. This is

River. 24 Feb 1969, W. W. Wirth (8 3, 5 9; contribution number 282 of the CCRE pro-

USNM); Milk River Bath, 1 1 Mar 1970, T. ject, which is partially supported by a grant

Farr, W. W. Wirth (7 6, 4 9; USNM); Rio from the Exxon Corporation. 756 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON

Literature Cited gy—Adults, pp. 9-63. In McAlpine. J. F., et al., eds.. Manual of Nearctic Diptera. Ottawa. [Vol-

Cresson, E. T., Jr. 1944. Descriptions of new genera ume 1 is Monograph 27 of Research Branch Agnc. and species of the dipterous family Ephydridae. Canada.]

Paper XIV. Notulae Nat. Acad. Nat. Sci. Phila- Runyan, J. T. and D. L. Deonier. 1979. A compar- delphia. 135: 1-9. ative study of Pseiidohecamede and AUotnchoma

. 1946. A systematic annotated arrangement (Diptera: Ephydridae). pp. 123-127. In Deonier, of the genera and species of the Neotropical D. L., ed.. First Symposium on the Systematics

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