382 



UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



Wings: The wings are nearly hyaline, with a very 

 faint brownish tinge, wholly villose, except in parts 

 of the costal and basal cells. First posterior cell 

 rather narrowed to half of its maximal width, second 

 posterior cell of uniform width. Fourth posterior cell 

 closed with a short stalk and a little shorter than the 

 discal cell. Anal cell closed with a short stalk. The 

 anterior crossvein enters the discal cell before the basal 

 fourth. Alula narrow. The ambient vein ends at or 

 just beyond the first posterior cell but is weak behind 

 the apex of the wing. Basal setae of the costa unusually 

 long. 



Abdomen: The abdomen is comparatively slender, 

 widest on the first segment, which is as wide as the 

 mesonotum. Whole abdomen coarsely punctured and 

 strongly corrugate in lateral profile, each tergite con- 

 vex. The abdomen is shining black with a small, post- 

 marginal triangle or band in each posterior corner 

 on the second to fifth tergites, silvery white or greyish 

 in color. Pile moderately abundant, suberect, coarse, 

 blackish over the middles of the posterior tergites, 

 yellowish at the base of the second to fourth tergites, 

 longer and yellowish white on the posterior margin 

 of the sixth tergite. A narrow lip of the seventh tergite 

 shows dorsally in the male. Lateral margins of the 

 first tergite with 6 quite stout, long, pale, yellow bristles 

 in a single, close-set row. Bristles absent on remain- 

 ing tergites, though the hairs on the sides of the second 

 tergite are rather stiff. 



Type: Male, Distrito Federal, Eio de Janeiro, Bra- 

 zil, October 1937 (Servicofevre, Amarella, M.E.S. 

 Brasil). In the collection of the Departamento de 

 Zoologia, Secretaria da Agricultura, Sao Paulo, Brazil. 



Genus Aphestia Schiner 



Figures 202, 648, 1195, 1204 



Apliestia Schiner, Verb, zool.-bot. Ges. Wien, vol. 16, p. 673, 1866. 

 Type of genus: Atomosia annulipes Macquart, 1838, as 

 Aphestia brasiliensis Schiner, 1S66, by original designation. 



Flies of less than medium size. Characterized by the 

 narrow face, the small, slender proboscis, the appressed 

 setate pile of the mesonotum and abdomen and the 

 stout marginal bristles upon the tergites and especially 

 by the quite long and quite slender antenna. The meso- 

 pleuron has long, stout bristles in the upper posterior 

 corners. Length 10 to 13 mm. 



Head, lateral aspect: Face narrowly visible on the 

 upper half, gradually becoming a little more extensive 

 below where it is gently and obtusely rounded. The 

 eyes are strongly convex anteriorly and nearly plane 

 posteriorly throughout the middle. The occiput is 

 shallow in the middle, obliterated on the upper fourth 

 but more prominent below; the pile is scanty through 

 the middle and at the upper corners but becomes longer 

 and more abundant ventrally. Stout bristles begin at 

 the lower third and consist of 15 pairs with some weaker 

 ones which lie directly in the middle of the occiput. 

 Proboscis small, slender, subcylindrical, with the base 



gradually swollen from the dorsal aspect. The apex 

 is tapered dorsally to a blunt point and bears dorsal and 

 ventral pile. Base with a few long hairs laterally and 

 ventrally ; medial dorsal ridge quite low. Palpus clear- 

 ly of two segments ; the first segment is short, excavated, 

 distinctly fused to the base, the second is longer, clavate, 

 not porate, and bears stiff bristles at apex and other 

 long hairs laterally and ventrally; hairs also present 

 on the first segment. The antenna is attached at upper 

 third, the first segment is iy 2 times as long as the sec- 

 ond, cylindrical, the second segment beadlike. The 

 third segment is exceptionally long and slender, of uni- 

 form width. Just beyond the middle dorsomedially 

 it has a shallow incision and conspicuous spine; apex 

 of segment bluntly rounded but sharper dorsally ; this 

 segment 2 1 /o to 3 times as long as the first two combined. 

 First segment of antenna with several stiff setae dor- 

 sally on the apical half and with a single, long bristle 

 ventrally near the middle and additional shorter, stiff 

 hairs. Midborder of the second segment with 4 stiff 

 setae above and 6 below. 



Head, anterior aspect : The face below the antenna is 

 a sixth of head width, widening below. Subepistomal 

 region small, short, oblique, deeply concave and bare. 

 The face is pubescent and bears, besides some stiff short 

 pile on each side a vertical row of bristles which are 

 partly doubled ; those on the upper half of the face are 

 short, those on the lower half much stouter and longer: 

 all are strongly curved obliquely downward. The pile 

 is distributed chiefly along the lateral margin with a 

 few, scattered hairs in the middle portion above. In 

 the middle portion may be some weak bristles. Front 

 narrowly divergent, the vertex slightly convergent ; the 

 front bears along the eye margin 4 or 5 weak bristles. 

 Vertex deeply excavated, with slanting sides. Ocel- 

 larium moderately large, with vertical or nearly ver- 

 tical sides and bearing a pair of stout, long, divergent 

 bristles. Eye facets considerably enlarged. 



Thorax: The mesonotum is pubescent only along 

 lateral margins, on humerus and, on whole of pleuron. 

 Mesonotal pile dense, short, curled and setate ; the sur- 

 face is punctulate. Humerus pilose. The long, stout, 

 lateral bristles consist of 1 notopleural with sometimes 

 an additional bristle anteriorly, 1 supraalar with some- 

 times weak, shorter ones above the postalar, 1 or 2 post- 

 alar, 1 or 2 pairs of stout, long scutellar bristles. 

 Scutellar rim impressed; surface convex, with numer- 

 ous, stiff, curled hairs arising from punctures. Pleuron 

 with abundant, fine pile on all portions ; pronotum with 

 6 pairs of weak bristles; mesopleuron with long, stiff, 

 scattered pile over almost the whole surface and bear- 

 ing in the upper posterior corner 3 long, stout bristles. 

 Upper and anterior stemopleuron, anterior and pos- 

 terior hypopleuron each with a group of long, stiff 

 hairs. Pteropleuron apilose ; metapleuron with a wide, 

 oval, patch of numerous, long, slender, weak bristles 

 with, besides pile, a single, vertical row of 7 stout, long, 

 black bristles. Metanotal slopes with abundant, long 

 pile. Metasternal slopes densely long pilose ; metaster- 

 num with long, scant pile; postmetacoxal area chitin- 



