LIBRARY OF THE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN 590.5 FI v. 44 cop. 3 NATURAL HISTORY. SURVFY 7X/iJ. FIELDIANA ZOOLOGY, JUN 71965 Published by CHICAGO NATURAL HISTORY MUSEUM Volume 44 September 29, 1964 No. 19 New Species of Leptocera Olivier In the Burrows of the Pocket Gopher, Geomys Bursarius Illinoensis Komarek and Spencer, found in Illinois (Diptera: Sphaeroceridae) O. W. Richards Imperial College of Science and Technology, London I am much indebted to Dr. R. L. Wenzel of Chicago Natural History Museum for allowing me to examine these interesting speci- mens which raise some difficult but basic taxonomic problems. Leptocera (Limosina) semioculata, new species. Figures 26, a; 27, a; 28, a-c. A male and a female (described from alcohol). Black or brown, halteres pale, knob a little darker in mature specimens. Wings hyaline. Antennae with normal bristles and pubescence, arista four times as long as antennae with moderately long pubescence, first segment five times as long as broad. Eyes rather small, buccae at vibrissal angle half as wide as vertical diam- eter of eye, posteriorly as wide as this diameter. Head bristles normal, four pairs of interfrontal bristles of which the second pair is much larger and crosses, anterior orbital half the length of the posterior one. Mesoscutum with one humeral bristle, two pairs of posterior dorsocentrals between which are about eight rows of acro- stichals. Scutellum not at all reduced, about as long as broad, with four bristles, apical pair much longer than the scutellum. Sternopleuron with one bristle and one or two minute setae. Wings with alula narrow, R 2 + 3 very slightly sinuous, bending gradually onto the costa. R 4 + 5 straight, not overpassed by the costa, ending just in front of the wing-tip, second costal sector scarcely longer than third, intermedian cell somewhat long and narrow, both issuing veinlets short, interme- dian cross-vein well removed from r-m. Forelegs normal. Midlegs with tibia bearing an anterodorsal bristle at one-third with a minute bristle above it, a dorsal bristle surmounted by a minute seta at six-sevenths, somewhat above the dor- sal bristle a rather smaller posterodorsal and just above that an anterodorsal, ven- trally with a bristle at one-half and an apical bristle; basi tarsus long, more than half as long as tibia, with short fine setulae beneath. Hind legs with no unusual Library of Congress Catalog Card Number: 6b~25823 UAL ..... :.k>-*/ SURVEY No. 980 141 Fttf ZZ lytjb 142 FIELDIANA: ZOOLOGY, VOLUME 44 Fig. 26. a, Leptocera semioculata sp. nov., left wing (length 2.5 mm.); b, L. nidicola sp. nov., left wing (length 1.4 mm.). bristles, basitarsus longer and narrower than usual, second segment of tarsus also rather long. Male with no special leg-bristles. Abdomen fully sclerotized without long bristles. Female abdomen with 6 normal transverse tergites after 1 +2, ninth rounded triangular; cerci in dorsal view narrowly triangular with a long nearly straight apical bristle and a shorter one above it. First six visible sternites normal and transverse, apical ones beyond this interrupted centrally by membrane. Male abdomen with 4 normal tergal plates (1 +2, 3-5), tergite 6 triangular and confined to the left side, tergite 7 large but not quite reaching the right side and without long bristles; genitalia with a long bristle on each side above the anal split which is wide, especially below, and is fringed with widely spaced bristles of moderate length. Fifth sternite with a more transparent semi-circular preapical area through which a dark longitudinal strut can be seen, beyond this a pair of transverse rec- tangular plates which project obliquely downward from the surface of the sternite and each bear 3-4 transverse rows of minute comb-like setae, sternite also with some longish bristles on the left side and also another semi-circular membranous patch in the posterior margin. Genitalia with genital forceps produced about half- way along its inner dorsal edge into a short black spike, edge beyond this emargi- RICHARDS: NEW SPECIES OF LEPTOCERA 143 nate in dorsal view; apex of forceps truncate or feebly emarginate according to view. Posterior gonapophyses narrow, curved somewhat downward and inward. Aedeagus in dorsal view widened distally, with a central process and on each side two lateral processes. Measurements. Male, 2.3-2.7 mm. long; female, 2.1-2.3 mm. long. Holotype. A male from Illinois, Kankakee County, between Hopkins Park and St. Anne, collected from molasses trap in bur- row of Geomys bursarius illinoensis, May 28, 1946 by R. L. Wenzel and H. S. Dybas. Allotype. A female, same data as holotype, Paratypes. 1 male, 2 females, same data as holotype. Two males, 2 females, same data as holotype but collected May 28-29, 1946 by H. S. Dybas and R. L. Wenzel. Types in Chicago Natural History Museum, some paratypes in my collection. Remarks. The species might also fall within Spuler's subgenus Spelobia but the eyes are somewhat larger. However, that sub- genus should probably be sunk to Limosina Macquart (see p. 146). Spuler (1925, p. 70) lists four species of the subgenus Limosina Macquart (=his Scotophilella Duda) as having small eyes. These four differ from the present species as follows: Leptocera varicosta Malloch, 1914, has yellow antennae and a black second costal seg- ment. Leptocera mirabilis, Collin, 1902, has a long curved spur on Fig. 27. Heads of (a) Leptocera semioculata sp. nov., from left; and (6) L. typhlops sp. nov. 144 FIELDIANA: ZOOLOGY, VOLUME 44 the hind tibia. L. gracilipennis Spuler, 1925, has the cheeks at the vibrissal angle three-fourths as high as the eye, the median cell very- long and narrow and the costa surpassing the third vein (R 4+5 ). L. cellularis Spuler, 1925, has four pairs of interfrontal bristles none of which is cruciate; arista just over two not four times as long as the antenna; the second costal sector seems to be relatively longer compared with the third. Among European species, L. racovitzai Bezzi var. microps (Duda) has reduced eyes and lives in underground mammal runs, but R^s is somewhat sinuous and the posterior corner of the intermedian cell is rounded. In Duda's key to the world species of Leptocera subg. Limosina (his Scotophilella) (1925, p. 153) it runs to couplet 64 but although the alula is narrow, the bristles on the lower part of the mid-tibia are not paired. 0.25mm Fig. 28. Leptocera semioculata sp. nov., a, d* fifth sternite in ventral view; b, d 1 genitalia in dorsal view; c, d" genitalia from right. Leptocera (Limosina) typhlops, new species. Figures 27, b; 29, a-c. A male and a female (described from alcohol). Usually with rudimentary- wings (shorter than the scutellum) and reduced halteres, but rarely fully winged. Reduced form described first. Light brown with a paler stripe down the center of the mesoscutum and scutellum but all specimens are perhaps immature. Halteres whitish. RICHARDS: NEW SPECIES OF LEPTOCERA 145 Antennae with normal bristles and pubescence, arista five times as long as antenna with moderately long pubescence, first segment five times as long as broad. Eyes very small, no larger than the silhouette of the third antennal seg- ment, buccae at the vibrissal angle nearly twice as wide as the vertical diameter of the eye. Ocelli normal. Head bristles normal, three pairs of interfrontals of which the second is larger and cruciate, both orbitals of the same length, rather short. Mesoscutum not reduced, about as wide as the head, with one humeral bristle, two pairs of postsutural dorsocentrals, anterior pair very small, and about eight rows of acrostichal bristles between them. Scutellum not at all reduced, nearly as long as broad, with four bristles, apical pair much longer than the scutellum. Sternopleuron with one bristle and one small seta. Wings pad-like, from half as long to nearly as long as the scutellum with two short but quite stout costal bristles. Halteres short, appearing sessile, with rather irregular outline but stalk distinct in macerated specimen. Forelegs normal, tarsi rather elongate. Midlegs with tibia bearing an anterodorsal bristle at one-third with a minute one above it, a dorsal bristle surmounted by a minute seta at six-sevenths, somewhat above this bristle a rather smaller post.erodorsal and just above that an antero- dorsal, ventrally with a bristle at one-half and an apical bristle; basitarsus long, more than half as long as tibia, with short fine setulae beneath. Hind legs with no unusual bristles, basitarsus and second segment of tarsus both somewhat longer than usual. Male with no special leg bristles. Abdomen fully sclerotized, with two moderately long bristles at the sides of tergal plates 1 +2 and 3, and one at the sides of 4-6. In female, tergite 7 normal, 8 gently emarginate posteriorly, 9+10 represented by a rounded triangular plate bearing two straight upright bristles, cerci elongate-triangular with one long and one shorter more dorsal bristle, both nearly straight; first six visible sternites normal and transverse, more apical ones centrally interrupted by membrane. Male abdomen generally very like that of Leptocera semioculata Rich, but differing as follows: plates at apex of central transparent area on sternite 5 much more transverse with only two rows of setae; genital forceps with inner black spikes smaller, apex of forceps not in any view emarginate. Aedeagus in dorsal view with the sides more rounded and convergent distally, central process transverse, lower of two lateral processes shorter. Long- winged form quite similar but wings and halteres normal, venation rather pale but exactly like L. semioculata Rich. Measurements. Male, 1.3-1.8 mm. long; female, 1.5-1.75 mm. long. Holotype. A male from Illinois, Kankakee County, 7 miles N.N.W. of Hopkins Park, in fecal chamber of Geomys bursarius illinoensis, May 20, 1948, collected by H. S. Dybas and R. Inger. Allotype. A female, same data as holotype. Paratypes. 27 males, 21 females, 1 sex doubtful (no abdomen, long-winged), same data as holotype. 3 males, 1 long-winged male, 2 females from Kankakee County between Hopkins Park and St. Anne, collected from molasses trap in burrow of G. bursarius illino- ensis, May 28-29, 1946, by H. S. Dybas and R. L. Wenzel. 20 males, 16 females (all but one male and one female very immature) from sandy area near Hopkins Park, collected from fecal chamber of G. bursarius illinoensis, May 21, 1951, by H. S. Dybas and R. L. Wen- 146 FIELDIANA: ZOOLOGY, VOLUME 44 zel. Three males, 2 females from 0.8 miles north, 5.7 miles east of St. Anne, sand dunes area, fecal chamber of G. bursarius illinoensis, May 6, 1953, collected by H. S. Dybas, H. G. Nelson, R. Ward, and R. L. Wenzel. Types in Chicago Natural History Museum, some paratypes in my collection. 0.25mm Fig. 29. Leptocera typhlops sp. nov., a,