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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



The remaining lateral bristles are exceptionally long 

 and consist of 3 notopleural, 3 supraalar, 2 postalar, 

 and 1 widely separated pair on scutellar margin; the 

 bristles of the last 2 groups are nearly twice as long 

 as the mesonotal height. Scutellar surface nearly flat 

 and micropubescent only. The propleuron bears abun- 

 dant pile; the upper lateral portion has 2 long bristles, 

 the collar with 7 or 8 pairs of bristles. Middle of meso- 

 pleuron and upper stemopleuron with a patch of long, 

 fine hairs. Pteropleuron and hypopleuron without pile ; 

 the latter has an appressed pubescent patch. Meta- 

 pleuron with a vertical row of 12 long, basally stout 

 bristles. Metanotal slopes bullose and micropubescent 

 only. Slopes of the metasternum with long pile. 

 Metasternum long pilose. Postmetacoxal area mem- 

 branous; tegula with some stiff setae. 



Legs: The legs are not thickened; the hind femur is 

 distinctly longer than the middle pair; its pile is sparse, 

 flat appressed and very finely setate with a scanty, erect 

 fringe below ; this femur bears only 2 bristles which are 

 lateral and located near the base ; its trochanter with a 

 single lateral bristle ; coxa with only quite stiff, bristly 

 pile. Hind tibia rather thickly appressed setate, the 

 medial surface with a dense brush of appressed setae 

 from the middle. This tibia is moderately long, with 

 stout, oblique bristles, 2 dorsal, 1 at the base, and 1 in 

 the middle; the apex contains 2 medial, 1 dorsal, 2 

 lateral, and 4 ventral elements. Hind basitarsus seven- 

 tenths the length of the remaining segments and with 

 very stout, long bristles. Middle femur with a stout, 

 posteroapical bristle and setae above beginning near the 

 middle and a few, fine hairs below. The midtibia bears 

 long, stout, oblique, dorsal and ventral bristles and 

 shorter ones between posteriorly. There is 1 anterior 

 subbasal bristle, 4 anterodorsal, the last 2 exceedingly 

 long, 4 short posterodorsal, 4 equally short postero- 

 ventral, 2 long ventral bristles. Anterior femur with 

 a posteroapical bristle, its tibia has only short bristles 

 except below ; they consist of 6 anterodorsal, 5 postero- 

 dorsal, 4 posteroventral, and 2 long ventral elements. 

 The apex medially bears a long, stout, inwardly curved, 

 pointed spine. The adjacent area of the basitarsus 

 microtuberculate. All tarsi bear long pulvilli; long, 

 basally thickened empodium and moderately sharp 

 claws. 



Wings : The marginal cell is open ; anterior branch of 

 third vein ends well before the wing apex; fourth 

 posterior cell closed with a short stalk. Anal cell closed 

 in the margin; second basal cell closed with 3 veins; 

 alula large, ambient vein complete. 



Abdomen: The abdomen is cylindroid and slightly 

 tapered, slightly longer than the wings. Tergite one 

 slightly thickened and barely wider than tergite two 

 and not as wide as the mesonotum. Pile of abdomen 

 fine, short, sharp and setate. Bristles present only on 

 the first tergite, where there are 6 pairs, long and quite 

 stout. Sternites with long, fine pile, except on the first 

 sternite, which is pubescent only or with a few, fine, 

 short hairs toward the lateral margin. In the male 

 eight tergites present, but the eighth rather short, half 



the length of the seventh dorsally, a third its length 

 laterally. In the female eight tergites present, the 

 eighth is three-fourths as long as the seventh. Male 

 terminalia prominent; epandrium short, broad and ob- 

 tuse, overlapping above. Gonopod shorter; hypan- 

 drium undivided. Terminalia not rotate. Female 

 terminalia with 6 or 7 pairs of spines on the acantho- 

 phorites. Ventral plate slightly compressed laterally 

 at apex into a scooplike structure which extends a little 

 beyond the spines. 



Distribution: Australian: Chylophaga australis 

 Ricardo (1912). 



Genus Questopogon Dakin and Fordham 



Figures 148, 182, 486, 965, 974, 1709, 1714, 1959, 19S6, 2044, 2048 



Questopogon Dakin and Fordham, Ann. Mag. Nat. Hist, ser. 9, 

 vol. 10, p. 525, 1922. Type of genus : Questopogon clarkii 

 Dakin and Fordham, 1922, by original designation. 



These are large and comparatively robust flies with 

 dense but short pile. All the cells of the wing are open. 

 These flies are quickly recognized by the pair of stout, 

 down-turned, spikelike bristles, on the ventral surface 

 at the apex of the midtibia, that distinguish them from 

 all asilids except the North American genus Callinicus 

 Loew ; from that genus they are separated by the pres- 

 ence of a double spine borne on a protuberance at the 

 apex of the anterior tibia. Length 25 to 35 mm. 



Head, lateral aspect : The head is of moderate length 

 but the eye is short and slightly wider above. The face 

 is well developed and convex; it is concave and oblique 

 from the anterior epistomal margin to the base. The 

 occiput is unusually thick and wide but is narrow above 

 and obliterated at the vertex. The occipital pile is long, 

 fine and very dense, reaching nearly to the eye margin ; 

 on the upper part are 3 fine, black bristles. The pro- 

 boscis is short but compressed, the tip bluntly rounded 

 and a little narrowed ; the apex has fine pile at the tip 

 and below and the base bears numerous, long, fine hairs. 

 The palpus clearly of two segments and with a trace of 

 the antepenultimate segment. First segment quite 

 short and excavated, end segment longer and held dis- 

 tinctly at an angle with offset attachment ; it is arcuate, 

 cylindrical, with numerous, long, bristly hairs extend- 

 ing to the apex and with a lateral apical pore. The 

 antenna is about 1*4 times the head length and attached 

 at the upper third of the head. The first two segments 

 are of equal length, 2 or 3 times as long as wide. The 

 third segment is longer than the combined length of the 

 first two segments; it is elongate, of uniform width 

 nearly to the apex but is a little narrowed on the apical 

 fifth ; this segment bears a very short microsegment fol- 

 lowed by a longer, conical, truncate spine tipped micro- 

 segment held at an oblique angle. The first segment 

 bears numerous slender bristles and bristly hairs on all 

 sides; these hairs are longer ventrally and fewer medi- 

 ally ; second segment with 1 long, stout, ventral bristle 

 and some stiff, bristly hairs; third segment with 3 or 4 

 long, dorsal and basal setae. 



