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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



bristly hairs with a smgle rather prominent apical 

 bristle. The antenna is attached at the upper third of 

 the head, rather slender and of moderate length. The 

 first segment is as long as the second, the second com- 

 paratively slender. The third segment is no wider than 

 the apex of the second and more narrow towards the 

 basal third; it is attenuate apically, its length equals 

 the combined length of the first two segments ; it bears 

 a short, distinct microsegment and a slender, bristle- 

 tipped style which is a little longer than the third seg- 

 ment. First segment with 10 or 12 slender, bristly 

 hairs laterally and ventrally, the second segment with 3 

 ventral bristles ; both with dorsal setae. 



Head, anterior aspect : The face below the antenna is 

 about a fourth the head width and wider below. Sub- 

 epistomal area moderately large, deejily concave, pubes- 

 cent, oblique. The face is pubescent, apilose, the middle 

 part has a wide band of stout bristles begimiing beneath 

 the antenna ; those of the upper half are chiefly black, 

 moderately long and strongly curled downward ; those 

 on the lower half are very stout, pale, extending to the 

 apex of the proboscis. Lateral margins of the epistoma 

 with numerous, slender, black bristles. Front short, 

 pubescent, with laterally an oval patch which contains 

 7 long, slender, marginal bristles and 8 others above 

 the antenna which are still longer. Vertex deeply ex- 

 cavated with vertical sides ; ocellariimi rather large, set 

 quite forward anteriorly, bearing 1 pair of slender, 

 black bristles between the ocelli and a pair between the 

 posterior ocelli and 2 pairs behind the ocelli. Anterior 

 eye facets enlarged. 



Thorax: The mesonotum is pollinose, abrupt and 

 convex both anteriorly and posteriorly. The pile of the 

 mesonotum is rather scanty, composed of stout, quite 

 short, finely pointed, suberect setae ; a fine row of very 

 short, acrostical elements is present. Anterior dorso- 

 central elements present and likewise extremely short, 

 but become long and quite stout behind the suture where 

 there are 7 or 8 in the outer row and 3 or 4 in the sub- 

 medial row. Humerus with fine, scanty pile. The 

 stout, lateral bristles present in the type of genus con- 

 sist of 2 notopleural, 2 supraalar, 2 suprapostalar, 3 or 

 4 postalar, and 1 pair of scutellar bristles. Scutellmn 

 pollinose, moderately thick and convex with an im- 

 pressed rim, and scattered, fine, bristly, discal pile and 

 a deep crease. The pleuron bears ratlier scanty, fine, 

 long pile; the anterior pronotum has 2 or 3 pairs of 

 bristles. The upper mesopleuron, the posterior and 

 anterior stemopleuron have only a few, fine, short 

 hairs ; dorsal pteropleuron with 3 or 4 fine hairs ; the 

 posthypopleuron has a vertical row of exceptionally 

 fine, long hairs. Metapleuron with a vertical row of 4 

 stout, moderately long bristles and some fine pile ; lat- 

 eral and ventral metasternum pilose; postmetacoxal 

 area membranous; tegula with setae; basalare pubes- 

 cent only ; squama with a multiple fringe. 



Legs : The femora are stout, the anterior and middle 

 pairs distinctly though only moderately swollen to- 

 ward the base. The dorsal, lateral, and anterior pile is 

 stiii', fine appressed and setate. In the tyi^e of genus the 



bristles present are comparatively short, quite stout and 

 in the hind femur consist of 4 latei-al, the last subapical 

 element in this row matched with a dorsal and dorso- 

 medial bristle; also 1 stout, apical dorsomedial, 8 ven- 

 trolateral', 8 ventromedial and 2 longer, medial bristles 

 near the base. The hind tibia has 1 medial bristle before i 

 the middle, 3 dorsomedial, 3 dorsolateral, 3 ventrolat- 

 eral bristles on the outer half; apex with 1 medial, 1 

 ventromedial, 2 ventral, 1 ventrolateral, 1 dorsolateral 

 bristle. Hind basitarsus comparatively short but as 

 long as the next 3 segments, which are quite short. The 

 middle femur has 5 or 6 posterior, 2 subapical postero- 

 dorsal, 6 anterior, 6 anteroventral, 7 posteroventral 

 bristles besides 3 or 4 additional ventral bristles at the 

 base, the whole gi'oup forming a loose cluster. The mid- 

 dle tibia has 2 short, posterodorsal bristles beyond the 

 middle, 3 short, posteroventral and a like number of 

 ventral elements. The anterior femur has 2 stout, pos- 

 terior bristles in the middle and 3 stout, posteroventral 

 on the basal half, together with 3 or 4 similar antero- 

 ventral bristles basally. The anterior tibia has 1 antero- 

 dorsal near the base which, together with 3 postero- 

 dorsal at the middle and beyond, are quite short and 

 weak; ventrally there are 3 rather strong, moderately 

 long, posteroventral bristles matched by 3 longer, ven- 

 tral elements. All tarsi end in stout, moderately sharp 

 claws, chiefly bent at the apex ; long, thin, spatulate pul- 

 villi and short, entirely slender empodium half as long 

 as the claws. 



Wings : The marginal cell is closed with a short stalk ; 

 subcostal cell is quite narrow, the marginal cell wide; 

 the anterior branch of the third vein ends a short dis- 

 tance above the wing apex, the posterior branch ends a 

 somewhat greater distance behind. Second posterior 

 cell widened at the base but gently ; f om-th posterior cell 

 closed with a rather long stalk; the anterior crossvein 

 enters the middle of the discal cell at the middle ; second 

 basal cells ends in 2 veins which are briefly fused. The 

 anal cell is closed and stalked ; alula large ; ambient vein 

 complete. 



Abdomen : The abdomen is elongate, distinctly longer 

 than the wing and as wide as the mesonotum basally or 

 sliglitly wider, and rather strongly tapered. Males have 

 eight tergites, the eighth only present laterally, widen- 

 ing below where it is more than half as long as the 

 seventh; the seventh tergite is of uniform width and 

 only a third as long as the sixth. The sides of the first 

 tergite are only a little produced. Pile of abdomen very 

 short, bristly and flat appressed, continued short on the 

 lateral margins ; the sides of the first tergite bear at least 

 3 quite stout, black bristles and 2 additional pale bris- 

 tles. Along the lateral, subposterior margin of the 

 second tergite is a row of 5 short bristles, the upper 3 

 are rather stout; the same margins on the third and 

 fourth tergites have shorter bristles and bristly setae. 

 Surface of the abdomen, including the posterior mem- 

 branes, pollinose. Sternites bear only fine setae, includ- 

 ing the first. Male terminalia with the superior forceps 

 quite elongate, blunt, and flattened at the apex, the leaf- 

 like sides appressed ; they are not rotate. The gonopod 



