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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



merous, long, coarse hairs. The antenna is attached to 

 the upper third ; the first two segments are quite short, 

 of equal length, beadlike, the third elongate and slen- 

 der, thickest close to the base, narrowed beyond and 

 gently attenuate towards the apex. The third segment 

 is 2 to 3 times as long as the first segments combined, 

 bears a short microsegment followed by a long 

 microsegment which resembles a fleshy style, and car- 

 ries a short, stiff setae above, but with several, slender, 

 quite long, opaque bristles below; the second segment 

 has an even longer dorsal bristle combined with other 

 setae and with ventrally a stout bristle longer than 

 the third segment ; combined also with 3 or 4 somewhat 

 shorter, weaker bristles. 



Head, anterior aspect: The face below antenna is 

 less than one-fifth the head width and is divergent 

 below. Face without micropubescence, densely cov- 

 ered to the eye margins with opaque, rather long, 

 bristly pile, shorter and subappressed along the eye 

 margin, longer below near the bottom of the eyes 

 where it is curled and directed straight downward. 

 Subepistoma quite small and horizontal. The front 

 is slightly divergent, the vertex of nearly the same 

 width, slightly wider, the eyes rising considerably 

 higher than the exceptionally large ocellarium. The 

 ocelli are large, protuberant and bear across the center 

 2 or 3 pairs of long, slender, bristly hairs, 6 or more 

 shorter hairs anteriorly, 3 or 4 long and 6 or more 

 shorter hairs posteriori}'. Sides of front with dense, 

 appressed, long, coarse pile. Eye facets exceptionally 

 enlarged. 



Thorax : The mesonotum with micropubescence only 

 narrowly above the wings ; for the most part, together 

 with the pleuron, bare. Pile of mesonotum of two 

 types : the first consists of numerous, scattered, rather 

 long, curled, stiff, suberect setae or bristly hairs, grow- 

 ing longer posteriorly and with acrostical and dorso- 

 central elements not or scarcely differentiated; the 

 second, which may also occur, consists of rather matted, 

 abundant, coarse, opaque, flat appressed, bristly pile, 

 in which there is a distinct, narrow acrostical band 

 present. Humerus with pile of both types. Moder- 

 ately long, stout bristles present as follows: 5 or 6 

 notopleural, 3 supraalar, 3 or 4 postalar, and some 12 

 pairs of slender scutellar bristles. Scutellar disc with 

 coarse, crinkled pile. Pleuron without pollen or pubes- 

 cence, as polished as glass. The propleuron has a dense 

 tuft of coarse, opaque pile; the collar has a multiple 

 row of stout bristles containing 15 or more pairs. Up- 

 per mesopleuron, the anterior prolongation of which 

 is strongly convex, and the sternopleuron with a tuft 

 of dense, coarse pile. Pteropleuron and hypopleuron 

 without pile. Hypopleural pubescent patch spot pres- 

 ent. Metapleuron with a wide band of numerous, long, 

 stiff, coarse, opaque hairs. Metanotal slopes micro- 

 pubescent only; metastemal slopes and the metaster- 

 num with considerable fine hair. Postmetacoxal area 

 membranous; tegula with 8 to 10 long, stiff hairs 

 Presternum dissociated. 



Legs : All the femora stout, the hind femur especially 

 stout. All pile long, subappressed, coarse, and opaque. 

 The hind femur bears a transverse dorsal subapical 

 cluster of 4 bristles, and a dorsal row of 8 rather long 

 bristles ; ventrolaterally there are 8 or 10 long, slender, 

 bristly hairs. This tibia has stout, moderately long, 

 curved, oblique bristles : 6 dorsal, 5 dorsolateral, 2 ven- 

 trolateral from the middle. The medial surface has 

 a brush of setae but it is completely absent except on 

 the distal fourth. Apex with 12 stout spinous bristles, 

 of which 4 or 5 are medial. Middle femur with 2 

 strong and 2 or 3 weak anterior bristles and scattered 

 long hair ventrally, and matted rather long hair pos- 

 teriorly; the tibia has moderately long, sharp bristles 

 as follows: 3 dorsal, 4 or 5 anterodorsal, 6 posterior, 

 and 3 or 4 posteroventral. Anterior femur with 1 or 2 

 short, stout dorsal and anterior subapical bristles, the 

 tibia with 5 strongly appressed, stout, dorsal, 4 similar 

 posterodorsal, 4 posterior, and 4 ventral bristles, and 

 a medial brush of setae. Apex without spine. Tarsi 

 end in more or less apposed, long, rather slender, sharp 

 claws curved from the base; pulvilli absent or reduced 

 to minute stubs ; empodium present, about three- fourths 

 as long as the claws. 



Wings: The wings are hyaline; the marginal cell 

 widely open and wide apically; anterior branch of 

 third vein ends well above the wing apex, the costa 

 likewise; the ambient vein is absent. All remaining 

 veins atrophied some distance from the wing margin; 

 first and fourth posterior cells closed. The second sub- 

 marginal cell may be with or without a spur vein at 

 its base. Alula large; second basal cell ends in three 

 veins. 



Abdomen : The abdomen is short and robust, as wide 

 as the thorax, distinctly shorter than the wings. First 

 tergite not swollen. There are six tergites present in 

 the male, the seventh completely concealed beneath the 

 sixth. Females with six, or with the seventh protrud- 

 ing as a narrow lip. Pile of abdomen abundant, coarse, 

 opaque, flat appressed. There is some longer, similar 

 pile, more or less erect, which lies laterally and along 

 the posterior margins of at least some of the segments, 

 especially the terminal segments. True bristles absent. 

 Sternal pile long, fine, erect and abundant. Male ter- 

 minalia deeply recessed beneath the overlapping sixth 

 and seventh tergites. The rather large proctiger and 

 the slender, acutely pointed elongate posterior processes 

 of the gonopod protrude from beneath and may be 

 seen from the dorsal aspect. Epandrium simple and 

 uncleft and unnotched. The gonopod is rather en- 

 larged and expanded basally and well separated with 

 long, posterior process. The hypandrium forms a more 

 or less triangular plate which may be extended as a 

 posterior process. Female terminalia completely re- 

 cessed within the seventh tergite, which may appear 

 as a very narrow linear protrusion from beneath the 

 more or less cuplike sixth tergite. The female has 

 acanthophorites with on each side a row of slender, 

 sharp spines. 



