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UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



dorsally with slender, long, bristly hairs. Second seg- 

 ment with 3 or 4 long slender bristles dorsally and 

 ventrally. 



Head, anterior aspect: The face below antenna is 

 one-fourth the head width and divergent below. The 

 eyes descend below the cheeks. Subepistomal area com- 

 paratively small, concave and nearly horizontal. The 

 face is thinly pubescent with 10 to 12 short, curved, 

 bristly hairs on the plane section of the face lying be- 

 low ; the abrupt ventral gibbosity occupying the lower 

 three-fifths of the face carries quite numerous, long, 

 slender bristles extending far beyond the apex of the 

 proboscis, all of them are curved, attenuate, the upper 

 ones directed forward, the lower ones curled down- 

 ward. The front is short, pollinose, along the eye 

 margins with 4 or 5 exceptionally long, slender bristles 

 which are intermixed with 7 or 8 equally long, bristly 

 hairs. Vertex rather deeply excavated, the ocellarium 

 moderately large and high with steep sides and bear- 

 ing 2 or 3 pairs of long slender bristly hairs or very 

 slender bristles. Anterior eye facets strongly enlarged. 



Thorax: The pleuron everywhere minutely fiat ap- 

 pressed pubescent except on the lower middle meso- 

 pleuron and the middle of the sternopleuron where it 

 is polished and bare. Mesonotum bare and shining ex- 

 cept for a spot of pollen medial and adjacent to the 

 humerus. Length of mesonotum three times the height. 

 Pile of mesonotum densely short and appressed setate; 

 in it a considerable quantity of long, fine, erect, bristly 

 pile is intermixed. Acrostieal bristles undifferentiated, 

 dorsocentral bristles poorly differentiated and only 

 posteriorly. The following complement of bristles is 

 present laterally : humerus with a large, anterior tuft of 

 dense, bristly hairs; notopleuron with 1 to 3 long, quite 

 slender bristles; supraalar area with 3 long bristles and 

 additional long, stiff hair; postalar callosity with 4 

 bristles; scutellum with 10 pairs; all are long and 

 slender; scutellar disc with abundant appressed bristly 

 pile. Propleuron with a dense tuft of long, bristly 

 pile ; pronotal collar and posterior pronotum with sim- 

 ilar pile. The sternopleuron with a dense tuft of line, 

 erect pile, the upper and posterior mesopleuron with 

 abundant, long, bristly pile; posterior hypopleuron 

 with numerous, long, fine hairs; pteropleuron apilose. 

 Metapleuron convex, with a wide vertical band of long, 

 bristly hairs or slender bristles curled downward api- 

 cally. Lateral slopes of metanotum exceptionally bul- 

 lose, distinctly set off from the medial portion by a 

 sharp crease and micropubescent only. Lateral slopes 

 of the metasternum posteriorly with pile ; ventral met- 

 asternum quite wide, chitinized, micropubescent and 

 apilose; postmetacoxal area membranous; tegula with 

 long stiff setae. 



Legs: All the femora swollen, especially the hind fe- 

 mur, which is slightly concave ventrally and strongly 

 arched dorsally. The hind tibia is a little shorter, 

 cylindrical, strongly swollen at the base and becoming 

 only slightly wider apically, and distinctly arcuate. 

 The hind tarsi are relatively short and quite stout, the 

 hind basitarsus almost as large as the hind tibia. The 



dorsal pile of all the femora is abundant, consisting of 

 stout, appressed setae, but on the hind and anterior 

 femora are numerous, long, erect, bristly hairs inter- 

 mixed. Ventral fringe of the hind femur fine and quite 

 scanty on both the lateral and medial aspects; this 

 fringe on the hind tibia is erect, long and more abun- 

 dant. The following complement of bristles is present : 

 on the hind femur there is a row of 3 or 4 long, slender 

 curved bristles on the apical fourth, dorsomedially and 

 dorsolaterally ; on the hind tibia bristles are stout 

 basally; there are at least 8 dorsomedial; 10 dorso- 

 lateral, 4 or 5 fine, lateral, chiefly basal, and 4 or 5 ven- 

 trolateral, chiefly distal bristles. Middle femur with 

 3 or 4 anterodorsal bristles, besides a vertical anterior 

 apical row of 5 or 6 short weak bristles and similar 

 bristles posteroapically ; also with 2 closely adjacent, 

 longer subapical, posterodorsal bristles. Middle tibia 

 with well developed long bristles: 4 anterodorsal, 6 

 posterodorsal, with 2 additional shorter bristles at the 

 extreme base, and with 6 or 7 long, bristly hairs both 

 posterolaterally and posteroventrally, together with 

 other shorter bristly hairs intermixed. Anterior femur 

 on the outer third with long, slender bristles or bristly 

 hairs : 3 anterior, 4 or 5 dorsal ; its tibia with 10 short, 

 regularly spaced, anterodorsal, and 8 posterodorsal 

 bristles, besides 8 or 9 posterior and posteroventral 

 bristles. Anterior tarsus of normal length, the first seg- 

 ment as long as the next two. All tarsi end in stout, 

 sharp claws, long wide pulvilli, and a long swollen 

 bladelike empodium. 



Wings : Marginal cell open but narrowed. Anterior 

 branch of third vein ends just above the wing apex, the 

 posterior branch ends far behind the wing apex. First 

 posterior cell widely open, though slightly narrowed. 

 Fourth posterior and anal cells closed and stalked; 

 second basal cell ends in 3 veins, the middle vein half 

 as long as the upper vein. Alula of moderate width ; 

 ambient vein complete. 



Abdomen: The abdomen is as wide as the thorax 

 at the base, very slightly narrowing to the end of the 

 fifth tergite. The first three tergites only slightly con- 

 vex across the middle but in lateral profile ridged trans- 

 versely across the middles; these ridges are low and 

 convex but present a distinct, corrugated appearance. 

 The first tergite is three-fifths as long as the second, 

 and bears a dense tuft of fine pile. The abdomen begins 

 to be curved downward at the base of the fifth tergite. 

 There are six tergites visible in both male and female; 

 in females the seventh and eighth are completely con- 

 cealed beneath the sixth. Stemites with long, bristly 

 pile. Terminalia large, dorsally convex, extensively 

 open ventrally, the base of the gonopod swollen and 

 convex laterally. The epandrium is large, convex, con- 

 spicuous, bowllike, with deep, rounded, medial sulcus, 

 enclosing large, conspicuous proctiger. Gonopod later- 

 ally and basally exceptionally swollen and convex, with 

 two or three long, prominent, narrow processes. Clas- 

 per process also long, Hypandrium present but short 

 and obtuse. 





