186 



UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



PAKT 1 



Female terminalia with a row of at least 6 pairs of 

 quite fine, narrow, sharp spines with additional spi- 

 nous bristles laterally. Sternites with abundant, 

 dense tufts of long, bristly pile in the middle including 



the first stemite. 

 Distribution: Oriental: Toremyia scatophagoides 



Walker (1854). 



Genus Crobilocerus Loew 



Figukes 73, 538, 1007, 1008, 1721, 1972 



Crobilocerus Loew, Linnaea Entomologica, vol. 2, p. 533, 1S47. 

 Type of genus: Dasyyogon megilliformis Loew, 1847, by 

 monotypy. 



Medium srze flies which are exceptionally robust. 

 All cells of the wing are open ; the face is moderately 

 produced without being strongly gibbous and is very 

 densely pilose with bristles on the lower half. These 

 flies are long pilose on the thorax but short pilose on 

 the abdomen, except for its lateral pile. The bristles 

 of the legs are strongly developed. The antenna is 

 slender and elongate and the species are readily recog- 

 nized by the terminal microsegment which bears a tuft 

 of fine, long hair. Length 1 5 to 18 mm. 



Head, lateral aspect : The face is only moderately ex- 

 tensive, gently convex and retreating below. The eye 

 is short, distinctly recessive anteroventrally, beginning 

 to recede above the middle of the eye. Occiput unu- 

 sually dense and prominent and with dense, long, fine 

 pile throughout but longer and denser below. Among 

 the dorsal pile there are 10 to 12 pahs of stout, pale 

 bristles. Proboscis large, strongly compressed laterally 

 with a high medial ridge developed subbasally and con- 

 tinuing to the outer third or more narrowly nearly to 

 the apex. The proboscis is plane below but rather 

 strongly tapered above; the apex is bluntly rounded to 

 a point and bears fine, long, bristly pile for a short 

 distance above and more extensively below. The sides 

 of the proboscis near the base have 5 or 6 long, slender 

 hairs and a like number ventrally. Proboscis directed 

 obliquely downward. Palpus large and robust, the first 

 segment short and excavated, with fine, long pile below ; 

 the second segment is attenuate towards the apex, with 

 numerous, stout bristles ventrally and laterally but 

 only subapically; apex microporate. The antenna is 

 attached at the upper fourth of the head, long and 

 slender, the first two segments robust and short; the 

 first segment is only a little longer than the second, the 

 second almost spherical. The third segment is nar- 

 rower than the second, very slightly narrowed distally, 

 and with its microsegment is twice as long as the first 

 two segments. Microsegment held obliquely ; they are 

 2 or 3 times as long as wide, obliquely truncate at apex 

 and bearing a tuft of 5 or 6 bristly hairs; the apex also 

 has a dorsolateral spine. Front short, densely long, 

 bristly pilose laterally, leaving the middle narrowly 

 apilose. Vertex moderately excavated, with slanting 

 sides, the ocellarium large, high, and bearing 3 or 4 



pairs of fine, bristly hairs across the middle. Ocelli 

 large, anterior eye facets moderately enlarged. 



Head, anterior aspect: The face below antenna is 

 more than one-third the head width, with parallel sides. 

 Subepistomal area small, oblique, concave. The face is 

 very thinly pubescent, more or less bare in the middle, 

 densely covered on the dorsal half with long pile, on the 

 ventral half with numerous, equally long bristles ; the 

 lower elements are stout and not extended down the 

 sides of the short subepistoma. The front is short, 

 thinly and minutely pubescent but with a very large 

 patch of long, fine pile laterally leaving the middle 

 third bare. Front and vertex a little wider than face, 

 the vertex but little excavated. The ocellarium is large 

 with vertical sides, with large ocelli and 3 or 4 pairs of 

 long, slender hairs between the ocelli and several pairs 

 between the posterior ocelli. Anterior eye facets a little 

 enlarged. 



Thorax: The pleuron shining; mesonotum thinly 

 pollinose. Pile of mesonotum dense, fine, moderately 

 long and erect with a narrow band of acrostical hairs. 

 Dorsocentral elements clearly developed although the 

 prescutellar pile is a little longer. Humerus with 

 abundant, long pile and 4 bristles. The following 

 complement of lateral bristles is present in the type 

 of genus : 5 or 6 notopleural, 3 supraalar, the scutellum 

 with 6 or 7 pairs of more slender bristles and con- 

 siderable additional long pile. Scutellum slightly con- 

 vex with 3 transverse depressions. Propleuron densely 

 long, fine pilose; bristles absent, except on the collar, 

 where there are 4 or 5 pairs of slender bristles. The 

 upper border of the mesopleuron narrowly and the 

 upper posterior corner with considerable long pile; 

 there are 7 or 8 long, fine hairs on the lower corner of 

 the mesopleuron. Pteropleuron and sternopleuron 

 apilose; posterior hypopleuron convex and bearing a 

 large tuft of long pile; the very convex metapleuron 

 is widely covered with exceptionally long and abundant 

 fine pile and bristles are absent. Lateral slopes of the 

 metanotum micropubescent only. Posterolateral half 

 of the metasternum and the chitinized, convex and 

 ribbed ventral metasternum densely long pilose. Post- 

 metacoxal area membranous; tegula with bristly setae. 



Legs : The femora are quite stout without being swol- 

 len ; this is especially true of the last four. The dorsal, 

 lateral, and ventral surfaces of the hind femur have 

 very long, abundant, erect, fine pile. Bristles of the 

 legs unusually numerous ; they are stout, pale, oblique, 

 and of medium length. In the type of genus the fol- 

 lowing complement of bristles present: on the hind 

 femur 8 dorsolateral, 3 dorsal subapical and 3 dorso- 

 medial subapical, besides 2 similar medial bristles but 

 none along the ventral, ventromedial, or ventrolateral 

 surfaces. Hind tibia with 3 dorsomedial confined to 

 the outer half, 5 dorsal, 6 dorsolateral, with 7 or 8 

 lateral, besides 4 ventrolateral bristles. Ventral sur- 

 face with a brush of setae only at the extreme apex; 

 the medial surface has dense, long, fine, erect pile. 

 Middle femur with 7 bristles near the apex anteriorly 

 and dorsally and 2 or 3 posteriorly besides long, dense 



