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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



PAST 1 



The subepistomal area is large, oblique and fully as 

 long as the face, slightly concave and bare. Face pu- 

 bescent, apilose, with a single row of 4 pairs of very 

 stout, curved, rather long, anteriorly directed bristles 

 on the epistomal margin; some 2 or 3 pairs of finer 

 bristles may be added below these in some species or 

 the bristles may spread out over the lower third of the 

 face in 3 or 4 rows and including the more slender 

 elements may consist of at least 20 pairs. The front is 

 pollinose laterally with 2 longitudinal rows of nu- 

 merous, long, fine bristles, the outer row subocular in 

 position; the front is somewhat dilated in the middle 

 and is convergent again at the vertex; the vertex but 

 little excavated, the ocellarium low, ocelli large and 

 bears 3 pairs of slender bristles across the middle and 

 3 postocellar bristles. Eyes rather strongly enlarged 

 centrally. 



Thorax : The thorax is almost everywhere bare and 

 shining; a little humeral and prehumeral pubescence 

 and some anterodorsally may be present on the meso- 

 pleura. Pile of mesonotum moderately long, distinctly 

 bristly, sharp and more or less curved backward ; sim- 

 ilar bristly pile on the humerus, but longer. The fol- 

 lowing complement of bristles, long and stout is present 

 in the type of genus: 1 posthumeral, 2 notopleural, 2 

 supraalar, 2 postalar and 2 pairs of scutellar bristles ; 

 in some species 1 pair, in others 4 pairs. In all species 

 the scutellum is flat and at the base is fused smoothly 

 into the mesonotum. Propleuron with dense, long tufts 

 of stiff pile ventrolateral^ and a band of stiff pile pre- 

 ceded by a row of long, moderately stout bristles on the 

 pronotum. Other areas of pleuron apilose except the 

 hypopleuron has 1 or 2 hairs below and the metapleuron 

 with a narrow band of long, slender bristles and some 

 finer hair. Metanotal slopes micropubescent only; lat- 

 eral metasternum with pile divided in the middle by a 

 vertical crease, ventral metasternum with a narrow 

 band of chitin and numerous long hairs. Postmeta- 

 coxal area membranous ; tegula with bristles. 



Legs: All the femora are distinctly stout without 

 being swollen. Pile on the femora dorsally appressed, 

 rather short, fine and setate, becoming much more scanty 

 and changing to fine hairs below but moderately abun- 

 dant ventrally on the anterior femur. In the type of 

 genus the following complement of bristles is present, 

 most of them short but quite stout : on the hind femur 1 

 lateral at the base, no apicals; its tibia with 3 dorso- 

 medial at the basal fourth just before and just after 

 the middle, 3 lateral, 2 ventrolateral bristles with an 

 additional bristle close to the base. Brush of setae 

 present beginning near the base. Midfemur with only 

 long, bristly hair below; its tibia with 5 anterodorsal, 4 

 much shorter posterodorsal, 5 posteroventral, and 2 

 rather long, stout, oblique ventral bristles at the middle 

 and beyond. Anterior femur similar to the middle 

 pair; the tibia with 5 exceptionally stout, short, antero- 

 dorsal, 5 minute, posterodorsal, 4 posteroventral, and 1 

 ventral distal bristle. The apex has 2 long, stout dorsal, 

 1 posterior, 2 anterior, 2 ventral, and a conspicuous 

 stout spine arising from the protuberance and with 



basitarsal denticulae. All tarsi end in stout claws, 

 sharp, curved chiefly at the apex; long pulvilli and 

 moderately long empodium which is strongly swollen 

 cylindrically at the base. 



Wings : The wings are broad ; marginal cell widely 

 open; anterior branch of the third vein ends shortly 

 above the wing apex, posterior branch a short distance 

 behind ; first posterior cell widely open, fourth narrowed 

 slightly; anal cell widely open; alula of moderate 

 length ; ambient vein complete ; middle vein at the end 

 of the second basal cell is short. 



Abdomen: The abdomen is rather robust and more 

 or less flattened and as wide as the mesonotum ; shining 

 and bare, occasionally with narrow, posterior pollinose 

 fascia ; the pile is moderately abundant, but minute and 

 setate and becoming moderately long and quite fine 

 along the lateral margins. Sides of the first tergite 

 with 2 to 3 moderately stout bristles. Male with seven 

 tergites, the seventh reduced and only a third to a fifth 

 as long as the sixth tergite. Female with eight tergites, 

 the last two each slightly reduced, the eighth may be 

 less than half the length of the sixth. Male terminalia 

 moderately conspicuous, in the type of genus rotate 

 nearly a fourth and with the epandrium divided by a 

 V-shaped notch in the type of genus which is flared 

 rather widely ; the 2 halves are quite short and incon- 

 spicuous. The hypandrium below is extremely short, 

 leaving the lower structures open and cuplike. In some 

 species these structures are split to the base but not 

 flared. Female with 6 pairs of stout, long, pointed and 

 spoon-shaped spines upon the acanthophorites. Last 

 sternite compressed laterally to a ventral ridge which is 

 split to the base into 2 appressed flaps. Wings a little 

 longer than the abdomen. 



Distribution: Neotropical: Araiopogon cyanogaster 

 Loew (1851) [=pictu,s Philippi (1865)]; gayi Mac- 

 quart (1838) [ = chalybeiventris Loew (1851)]; fulvi- 

 cornis Macquart (1849). 



Apothechyla, new genus 

 Figure 1852 



Type of genus : Dasypogan carbo Walker, 1851. 



Robust flies with greatly reduced pile. The antenna 

 is elongate ; the third segment is without microsegment 

 and has an apical pit with concealed spine. Lateral 

 propleuron with very stout bristles. Scutellum also 

 with stout bristles. In the males the epandrium is fully 

 cleft and widely separated. Length 15 to 18 mm. 



Head, lateral aspect: The head is of medium length, 

 the face is extended for a short distance beneath the 

 antenna and is somewhat more extensive ventrally, but 

 the whole face is plane in profile. Cheeks are quite 

 short. Occiput prominent but only sublaterally; it 

 becomes more extensive toward the middle of each half. 

 The occiput bears rather abundant, coarse, long pile 

 below; distinctly stout bristles begin near the lower 

 fourth of the head and become very prominent along 

 the middle and above, and are continued behind the 

 vertex. About 20 pairs of bristles are present ; they are 



