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UNITED STATES NATIONAL MUSEUM BULLETIN 22 4 



distinctly enlarged and slightly compressed laterally; 

 it is arcuate and bears a dense band of very long, 

 oblique, brownish dorsal pile continued over the edges 

 of both medial and lateral margins, but shorter. There 

 is an equally conspicuous, ventral band from base to 

 apex. The tibia has 4 lateral and 2 dorsal long, stout, 

 curved bristles that protrude only a little way beyond 

 the long pile. Hind basitarsus swollen with long, dense 

 brush of oblique, brownish black pile dorsally. 

 Middle femur with a weak bristle anteroventrally at 

 the outer third and a still weaker bristle posterodor- 

 sally at the outer fourth. Its tibia has 4 long, stout, 

 curved, oblique, reddish bristles anterodorsally with 3 

 or 4 additional, shorter, more slender, black bristles 

 and more numerous, stiff, black bristly hairs. Pos- 

 terior surface with 2 long, yellow bristles on the outer 

 third, 2 more slender, equally long, black bristles near 

 the base; all of these are well mixed with dense, fine, 

 but stiff, black pile. 



Anterior femur without bristles but with fine, long, 

 blackish hairs dorsally, shorter appressed reddish 

 brown pile dorsally and similarly colored, fine, erect, 

 long hairs below; its tibia has inconspicuous bristles, 7 

 weak, fine, dorsal and a double row with additional, 

 fine, stiff hairs towards the base and other shorter hairs 

 intermixed. The outer two-thirds of the ventral sur- 

 face has a dense, brassy yellow mat and near the middle 

 4 quite long, fine, oblique, brassy yellow hairs, and on 

 the apical fourth 1 long, stout, quite flat appressed, 

 brassy bristle. Claws very strongly bent at the apex 

 to a right angle, arched and rather blunt; pulvilli 

 nearly as long as claw; empodium long and slender. 



Wings: The marginal cell closed with a medium 

 stalk. The anterior branch of the third vein is strongly 

 arched as its base, the whole vein slightly sigmoid. 

 First posterior cell open, only slightly narrowed. 

 Fourth posterior cell closed with a short stalk ; anal cell 

 likewise. The end vein of the discal cell and fourth 

 posterior cells are quite aligned. Alula narrow. The 

 ambient vein ends at the end of the second posterior 

 cell. 



Abdomen : The abdomen is broad and robust, wider 

 than the thorax; the base of the abdomen is slightly 

 more narrow; the whole abdomen is strongly arched 

 from a lateral profile and drooping, densely flat ap- 

 pressed, microscopically short pilose. The pile is 

 black, except postmarginally, where it is yellow, except 

 on the last tergite. Postmargins of second to fifth 

 tergites narrowly whitish, sides of first tergite with a 

 vertical row of 5 light brown, rather stout bristles. 

 Second tergite with a similar row of 5, the third tergite 

 with 5, the fourth with 3, the fifth and sixth tergites 

 with 2 bristles. There are seven tergites visible in the 

 female, sixth as long as the fifth, the seventh extremely 

 short, forming a narrow lip. Female terminalia com- 

 pletely hidden by the strongly cupped, distal portion 

 of abdomen consisting of two small, flaplike lobes. 



Distribution: Neotropical: Paratractia dasypus 

 Wiedemann (1828). 



Genus Epaphroditus Hermann 



Figures 2G1, 658, 1344, 1353, 2145, 2158 



Epaphroditus Hermann, Nova Acta Acad. Caes. Leop.-Carol., 

 vol. 96, p. 117, 1912. Type of genus : Laphria placens 

 Walker, 1SC5, by original designation. 



Rather small flies, distinguished by the slender 

 femora and tibiae with their long bristles, the short, 

 but erect brush of long, scaly pile at the ventral apex of 

 the hind tibia, the prettily banded wings, the rather 

 narrow face and the quite long, slender antenna in 

 which the third segment bears a dorsal incision with 

 spines at or before the middle. Moreover, the polished, 

 punctate, metallic abdomen of seven tergites bears 

 prominent lateral bristles and the postmetacoxal area 

 is arched and chitinized. The face is longer, more 

 narrow than in Atomosia Macquart but the principal 

 difference lies in the fact that the last tergites do not 

 form a pocketlike cup as they do in Atomosia. Length 

 10 to 11 mm. 



Head, lateral aspect : The face is almost or quite 

 plane with the eye margin on the upper half, but 

 slightly produced beyond the eye on the lower portion; 

 the whole face is nearly plane and slightly receding; 

 it is chiefly apparent in profile because of the mild 

 recession of the eye posteriorly. The face is compara- 

 tively high, the eye rather short and high and distinctly 

 narrowed below. The occiput is completely obliterated 

 laterally by the eye, except on the ventral recessive por- 

 tion ; the pile is only moderately abundant but coarse, 

 longer ventrally and with 10 short, weak bristles be- 

 ginning above the middle. The proboscis is small, 

 short, cylindrical, slightly constricted or narrowed in 

 the middle and barely longer than the face; it is trun- 

 cate apically and slightly oblique from below; the apex 

 bears numerous, long, stiff hail's on all sides. There is 

 a tuft of 3 or 4 slender, bristly hairs ventrolaterally 

 at the base and a low, transparent dorsal ridge on the 

 basal half; this ridge is characteristically directed 

 horizontally forward or slightly downward. Palpus 

 minute, short, cylindrical with 3 or 4 slender bristles at 

 the apex; the number of segments is not determined. 

 Antenna is attached at the upper third of head and is 

 unusually elongate and slender; the first segment is 

 about three times as long as the second, the second is 

 quite short. The third segment is approximately twice 

 as long as the first two combined and somewhat com- 

 pressed laterally, of uniform width; the apex is 

 straight below and arched to a blunt point apically; 

 this segment has a dorsal, spine-bearing incision. 

 First segment with 1 long, slender bristle in the middle 

 ventrally, another short bristle nearer the apex, and 

 some appressed bristly hairs ventrally and a few setae 

 dorsally. Second segment with a rather long group 

 of setae dorsally and ventrally. 



Head, anterior aspect: The face below antenna is 

 about a sixth the head width and slightly wider at the 

 epistoma. Subepistomal area quite small, concave, 

 slightly oblique. The face is densely appressed pubes- 



