DiSTPOOONINAE 



ROBBER FLIES OF THE WORLD 



169 



Abdomen : Comparatively short and robust, subcylin- 

 drical and generally rather convex. The abdomen at 

 base is approximately as wide as the mesonotum. Pile 

 of abdomen abundant but exceptionally fine. It is 

 rather long along the lateral margins, becoming shorter 

 and appressed towards the middle of the segment. The 

 abdomen is usually more or less shining black with con- 

 spicuous pale colored pollinose posterior fascia. Males 

 with seven tergites, the seventh quite short and more or 

 less concealed. Females with eight tergites, the fifth 

 and remaining tergites gradually shortened, the eighth 

 is comparatively short and perhaps less than one-third 

 the length of the fourth tergite. Female terminalia 

 with a circlet of stout, strong spines, 9 pairs on each 

 side of the acanthophorites. Male terminalia with 

 short, quite broad, medially cleft and apposed epan- 

 drium. The proctiger broad, short, polished, with pos- 

 terior protuberance. The gonopod of only moderate 

 length and size, with short posterior process, often 

 bearing a dense, terminal tuft of curved bristles and 

 bristly hairs. Hypandrium broad, short, but with ex- 

 ceptional depth. The male terminalia are rotate, usu- 

 ally about 90 degrees in dried specimens. 



Distribution: Nearctic: Ceraturgus aurulentus Fab- 

 ricius (1805) ; cruciatus Say (1823) ; elizabethae Brim- 

 ley (1924) ; mdbelae Brimley (1924) ; mitchelU 

 Brimley (1924); nigrlpes Williston (1886); similis 

 Johnson (1912). 



Neotropical: Ceraturgus fdimidiatus Macquart 

 (1847) ; geniculatus Bigot (1878) ; rufipennis Macquart 

 (1847). 



Palaearctic: Ceraturgus hedini Engel (1934) ; hawa- 

 murae Matsumura (1916). 



Locality unknown: Ceraturgus fandocides Walker 

 (1854). 



Malloch (1917) describes the larva of Ceraturgus 

 cruciatus Say. 



Genus Ceraturgopsis Johnson 



Figubes 122, 496, 1039, 1048, 1741, 1780, 1783 



Ceraturgopsis Johnson, Psyche, vol. 10, p. Ill, 1903. Type of 

 genus: Dasypogon cornutus Wiedemann, 1828, by original 

 designation. 



Rather large, robust species of flies with compara- 

 tively short pile but with pollinose bands and vittae 

 as in Ceraturgus Wiedemann. They are related to 

 Ceraturgus, differing principally in the type of an- 

 tenna and in the somewhat stouter femora and in the 

 presence of femoral clusters of bristles. Length 15 

 to 20 mm. 



Head, lateral aspect: Face rather prominent but 

 nearly plane; the eye is short especially above and 

 below, its profile gently rounded in front, bluntly 

 angulated in the middle behind so that the upper and 

 the lower halves are nearly plane. The eye is rather 

 strongly recessive anteroventrally. Occiput thick and 

 prominent, with dense, long pile in the middle and 

 lower half; replaced by stout, strong bristles on the 



upper part, consisting of some 25 pairs which are 

 straight. The proboscis is laterally compressed on the 

 apical half where it is gradually tapered; the apex 

 is bluntly rounded and bears stiff pile apically and 

 below and some long, slender bristles ventrally on the 

 basal half. It is directed obliquely forward and carries 

 a conspicuous medial ridge. Palpus with the first seg- 

 ment excavated, the second microporate, short, basal ly 

 stout, rather tapered towards the apex. The pile is 

 scanty and fine and restricted to the middle. Antenna 

 situated at the upper third of the head, long and slen- 

 der, longer than the head, the first two segments of 

 equal length, the third more than twice as long as the 

 first two. The third segment is somewhat compressed 

 laterally, of uniform width to its apex, where it bears 

 two microsegments, the first short and annular, the sec- 

 ond expanded until considerably wider than the first, 

 distinctly flattened, and in its flattened profile bluntly 

 rounded with attached dorsoapical spine. First seg- 

 ment, with numerous, stiff hairs ventrally, a few above, 

 the second with 2 moderately long, oblique, ventral 

 bristles and 2 dorsal setae, the third with a few dorsal 

 setae. 



Head, anterior aspect : Face below the antenna one- 

 third of the head width and slightly wider below. 

 Subepistomal area short, oblique, concave and bare. 

 Face densely micropubescent with dense, bristly hair 

 from antenna to epistomal margin, leaving only the 

 naiTow ocular margins bare. The bristles on the 

 lower third of the face are longer and a little stouter. 

 Front pubescent with dense, stiff pile laterally, the 

 vertex only moderately excavated, with very large, low, 

 ocellar protuberance which bears large ocelli and 5 

 pairs of stout, rather long bristles over the middle and 

 1 or 2 additional fine hairs. Eye facets centrally 

 enlarged. 



Thorax: The thorax is mostly pollinose, bare and 

 shining. The mesonotum is densely covered with long, 

 fine, suberect pile, a wide distinct band of acrostical 

 bristles followed by a narrow, bare stripe; dorsocen- 

 tral elements are undifferentiated except behind; in 

 front of the scutellum are 5 or 6 rather long pairs, 

 which are stout. There is a complement of stout, long, 

 lateral bristles as follows : 12 on humerus, 12 on noto- 

 pleura, 11 on supraalar, 6 on postalar, and 8 pairs on 

 scutellar margin. Scutellum flat and pollinose, with 

 a few scattered hairs. Propleuron with dense tufts 

 of long, fine pile, the posterior propleuron with 4 

 or 5 stout bristles. Posterior mesopleuron with abun- 

 dant, long, fine pile continued on the sternopleuron. 

 Hypopleuron and pteropleuron apilose. Metapleuron 

 with a wide, dense band of long, stiff bristly pile. 

 Metanotal slopes micropubescent only; lateral meta- 

 sternum pilose; metasternum proper chitinized, with 

 fine pile ; postmetacoxal area membranous ; tegula with 

 several bristles. Prosternum dissociated. 



Legs: The legs are rather stout, comparatively short, 

 the bristles numerous and well developed, the pile 

 rather short, appressed and dense. The following com- 

 plement of bristles is present: hind femur with 6 lat- 



