310 



UNITED STATES NATIONAL MUSEUM BULLETIN 224 



dilated apically but not compressed and bears an elon- 

 gate, apical spine. First segment below with 2 or 3 

 short setae, the third ventrally with 5 rather long, stout 

 setae and 1 or 2 short hairs dorsally. 



Head, anterior aspect : The head is wide and broad 

 ventrally with the dorsal aspect arched and compressed 

 so that it presents the appearance of being flared and 

 widened from the vertex downward. The eye extends 

 well below the cheeks. The face below the antenna is 

 a sixteenth the head width and strongly divergent at 

 epistoma, still more divergent at the bottom of the eyes. 

 Subepistomal area large, slightly convex laterally with 

 medial third depressed; this area concave, with a 

 narrow, medial ridge; the whole strongly oblique. 

 The face is pubescent, apilose, with 2 pairs of long, 

 slender, slightly curved bristles directed forward and 

 reaching the end of the proboscis. Front short, pubes- 

 cent with a little short pile laterally. The vertex is 

 narrow, slightly wider than the upper face, moderately 

 excavated ; its sides are nearly vertical. The ocellarium 

 is high, with vertical sides, the anterior ocellus quite 

 wide and more or less twinned; the whole is without 

 pile or bristles. Central eye facets greatly enlarged. 



Thorax: The thorax everywhere densely appressed 

 micropubescent. The mesonotum is strongly convex 

 anteriorly and distinctly overhangs the pronotum. 

 Pile of mesonotum scanty, fine, suberect, and bristly. 

 Acrostical elements appear to be absent; however, 

 anteriorly is a band of short, inconspicuous, dorso- 

 central, bristly hairs or setae which become somewhat 

 more abundant and slightly longer posteriorly. An- 

 terior margin of the humerus with 4 or 5 long, stiff 

 hairs. The following bristles are present: 1 long, 

 moderately stout notopleural ; 2 supraalar in a vertical 

 row, the dorsal element longer and stouter; 2 short 

 postalar with 6 or 7 additional, shorter, bristly hairs ; 

 and 10 pairs of slender, quite weak, scutellar bristles. 

 Scutellar disc flattened, pubescent with 2 or 3 bristly 

 hairs on either side, the basal crease deep. Propleuron 

 without pile, or bristles. Anterior sternopleuron with 

 a tuft of long, bristly hairs ; the upper margin of the 

 mesopleuron has similar hairs ; pteropleuron and hypo- 

 pleuron apilose; the metapleuron has a wide band of 

 long, rather numerous bristly hairs or very slender 

 bristles. Lateral slopes of the metanotum pubescent 

 only. The metanotum is short and vertical. Lateral 

 and ventral metasternum pubescent only. The post- 

 metacoxal area is certainly membranous, as it is 

 wrinkled. The whole metasternum is densely micro- 

 pubescent; its lateral margins have their limits clearly 

 defined both anteriorly and throughout. Tegula pubes- 

 cent only; squamal fringe minute and short. 



Legs: The femora, tibiae, and the basitarsi are all 

 comparatively elongate; the hind femur is gradually 

 and slightly dilated distally until it is 2 1 / i times the 

 basal thickness. This tibia is also gradually dilated 

 from the base until it is not quite twice the thickness of 

 the basal hinge and only a little thicker distally than 

 their basal fifth. The dorsal surface of the hind femur 



is covered throughout with a dense brush of extremely 

 fine, erect, rather long, brownish pile. The lateral and 

 ventral surfaces are covered with equally long, slightly 

 oblique, fine, golden pile which is a little shorter later- 

 ally. The immediate apex bears 4 slender, black bris- 

 tles ; 2 of these are lateral in position and 2 form a dor- 

 somedial row. Tibia as long as femur, slightly more 

 narrow toward the base, the dense, golden, oblique pile 

 below is short; there is more scattered, golden pile 

 above. This tibia bears 2 moderately long, yellowish 

 bristles ventrolaterally just beyond the middle. The 

 apex has 4 stout, black bristles, 1 dorsal, 1 lateral, 1 

 ventral, 1 medial. The hind basitarsus below has 8 

 rather long, stiff, black bristles with 5 additional bris- 

 tles at the apex and a few scattered, appressed, ventral, 

 yellow hairs. Midfemur three-fourths as long as hind 

 femur with moderately long, bristly pile anteriorly ; its 

 apex bears 7 or 8 long, fine, black, bristly hairs dorsally 

 and posterodorsally. Midtibia with a posterior row of 

 7 or 8 fine, long, slender, yellow bristles. 



Anterior femur shorter than the other femora, also 

 slightly thickened distally with 3 minute bristles at 

 the dorsal apex. Anteriorly near the apex there is 

 a tuft of 12 or 15 rather long, yellow hairs, including 

 2 or 3 weak bristles; the dorsal surface has a band of 

 short, fine, dark pile. Tibia with long, oblique, golden 

 pile anteriorly and with 3 or 4 short, brown bristles 

 posteriorly near the apex. Ventral apex with 6 rather 

 long, stout, black bristles and 1 or 2 shorter bristles 

 above on each side anteriorly and posteriorly. Basi- 

 tarsus with several stout, black bristles; the medial 

 row is relatively short, the anterior and posterior area 

 with longer bristles which are especially long anteri- 

 orly on the first 4 segments. Claws long, rather sharp 

 but gently curved throughout their length and not 

 strongly bent at apex. Pulvilli absent. Empodium 

 very stout, laterally compressed and half as long as 

 claw. 



Wings : The marginal cell widely open. All posteri- 

 or cells and the anal cell widely open. The second basal 

 cell ends with only 2 veins, the angle acute. The vein 

 at the upper end of the third posterior cell is rectangu- 

 lar and nearly as long as the oblique vein at the upper 

 end of the second posterior cell. Wings often diffusely 

 banded with brown. Ambient vein complete; alula 

 absent; the posterior basal margin of the wing is 

 fringed with rather long pile. 



Abdomen: The abdomen is subcylindrical ; gradu- 

 ally and distinctly widened so that the fifth to seventh 

 tergites are about iy 2 times as wide as the basal tergites. 

 There are eight tergites visible in female. Sides of 

 the first tergite have a row of numerous, stiff, black 

 hairs ; sides of second tergite laterally with many fine, 

 erect hairs; remaining tergite only with short pile. 

 First sternite distinct, pubescent only. Remaining 

 sternites with a few scattered, bristly hairs posteriorly. 

 Basal two-thirds of the second sternite with pubescence 

 only. Female terminalia extremely short, recessed 

 and inconspicuous. A small liplike portion extends 

 beyond the eighth tergite. 



