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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



the apex; pulvilli well developed, empodiuni pubescent 

 and swollen at base. 



Wings : All of the cells in the wings including the 

 anal cell widely open. 



Abdomen : The abdomen is cylindroid with parallel 

 sides, bare or pollinose, and with a bare appearance due 

 to the greatly reduced, fine, scattered, setate, subap- 

 pressed pile which characterizes most species. Some- 

 times the pile is longer laterally and marginally upon 

 the tergites. Males with seven tergites, the seventh 

 quite short and sometimes nearly concealed. Females 

 with eight tergites but with the eighth quite short and 

 almost concealed; the seventh tergite, however, large 

 and long. Only the first tergite with bristles laterally 

 which may be stout and quite numerous or placed by a 

 tuft of bristly pile. Male terminalia generally fully 

 rotate. The epandrium is moderately long, cleft to the 

 base, each half more or less triangular, shieldlike, and 

 apposed. Gonopod moderate in extent, the hypandrium 

 large but quite short, being turned upward as a blunt, 

 obtuse plate. Female terminalia with a row of stout 

 spines on the acanthophorites. 



Distribution: Nearctic: Callinicus calcaneus Loew 

 (1872) ; pictltarsis Bigot (1878) ; pollenia Cole (1919) ; 

 vittatus Wilcox (1936). 



Genus Ceraturgus Wiedemann 



Fiqukes 105, 521, 966, 975, 1781, 1788 



Ceraturgus Wiedemann, Analecta entomologica . . . , p. 12, 

 1824. Type of genus: Dasypogon aurulentus Fabricius, 

 1805, by nionotypy. 



Medium size or large species with drooping head 

 and abdomen, the latter comparatively robust and 

 cylindroid. Flies which frequently have conspicuous, 

 pollinose, abdominal fascia and mesonotal vittae. They 

 are readily recognized by the characteristic and ex- 

 ceptionally elongate antenna, much of which is due to 

 the extra terminal segments attached to the third an- 

 tennal segment. The first of these additional segments 

 is usually quite short, the second as long as the preced- 

 ing two segments together and densely short plumose. 

 Length without antenna 15 to 25 mm. 



Head, lateral aspect: Head of medium length, the 

 face prominent, both above and below, but nearly plane 

 or very slightly convex and nowhere extended or gib- 

 bous. The occiput is quite thick or prominent except 

 at the vertex, but its thickness increases rapidly from 

 the eye margin. Pile of occiput dense. Proboscis stout, 

 distinctly compressed laterally, the apex blunt and the 

 base below with 3 or 4 pairs of long, slender bristly 

 hairs. Palpus clearly of two segments, the first segment 

 hemicylindroid, the second porate and both with nu- 

 merous slender bristles and bristly pile. Antenna at- 

 tached at the upper fourth of the head, much longer 

 than the total head length, the first and second seg- 

 ments tend to be subequal and together about half as 

 long as the third segment considered without its addi- 

 tional terminal segments. The third segment bears 



terminally a short, robust segment, which is at least as 

 long as wide, and beyond this a remarkably long, ex- 

 tensive, flattened, somewhat wider and bluntly pointed 

 segment which is densely short plumose on all surfaces. 

 This final terminal segment is approximately as long 

 as the whole remainder of the third segment. 



Head, anterior aspect: The face at antenna is about 

 two-fifths the total head width, very slightly wider be- 

 low. Face densely micropubescent with bristly pile on 

 the upper half extending nearly to the antenna, and 

 below similar pile and slender bristles which become 

 considerably longer above the epistoma. The subepis- 

 tomal area is large, oblique, and nearly plane. Front 

 quite short, raised medially, pollinose and bristly pilose 

 laterally. The vertex is moderately but distinctly ex- 

 cavated, the ocellarium large, broad and low and bear- 

 ing 3 or 4 pairs of long slender bristles and additional 

 pile. Anterior central eye facets strongly enlarged. 



Thorax: Mesonotum rather bare, for the most part 

 feebly shining and with some opaque stripes; the hu- 

 meri, the lateral margins, and part of the scutellum 

 usually pale pollinose. The pile is very fine and sub- 

 erect with a medial acrostical band and an equally nar- 

 row dorsocentral band expanded anteriorly and with a 

 complement of rather weak bristles as follows : no hu- 

 meral, 2 notopleural, 3 to 5 supraalar, 3 postalar, and no 

 scutellar. The scutellum is gently convex with trans- 

 verse basal crease and a band of fine, rather long mar- 

 ginal pile. The pronotal collar bears a band of long, 

 bristly pile, the lateral pronotum and propleuron with 

 only tufts of long, abundant pile. The posterior half 

 of the mesopleuron and upper sternopleuron with a 

 wide conspicuous vertical band of long, slender bristly 

 hairs or weak bristles. Metanotal callosity micropubes- 

 cent only. Lateral and ventral metasternum with long 

 pile; postmetacoxal area membranous. 



Legs: The femora are stout without being swollen 

 and bristles are nearly absent. The hind femur bears 

 5 weak dorsolateral bristles and no apical bristles, the 

 middle femur bears 1 or 2 anterobasal bristles, the an- 

 terior femur usually none. Pile of femora fine, rather 

 strongly appressed on the hind pair, a little longer, 

 more delicate and more nearly erect on the first and 

 second pairs. All the tibiae bear somewhat longer, 

 stout, attenuate bristles: hind pair with 7 or 8 dorso- 

 medial, 6 dorsolateral, the apical cluster contains 14, 

 of which 1 is dorsal, 4 are medial, and the remainder 

 ventral and lateral; middle tibia with 5 anterodorsal, 

 4 anteroventral, 7 or 8 quite short, weak posterodorsal, 

 and 5 to 7 posteroventral bristles. On the anterior tibia 

 the dorsal bristles are quite short. There are 7 or 8 long 

 posteroventral bristles, those beyond the middle quite 

 stout, and ventrally there is a double row of excep- 

 tionally long bristly hairs. Protibia without spine at 

 apex. All the tarsi characteristically short, including 

 the basal tarsal segment. Claws stout, sharp, strongly 

 curved on the outer half, the pulvillus well developed, 

 the empodium bladelike and pubescent. 



Wings: Marginal and all the posterior cells widely 

 open ; anal cell narrowly open or closed in the margin. 



