DASTrOfiONINAB 



ROBBER FLIES OF THE WORLD 



137 



wings are smoky brown with a notch at the anal cell 

 and at the end of the fourth posterior cell. 



Abdomen: The abdomen is robust, wider than the 

 mesonotum, but scarcely as wide as the thorax. The 

 abdomen has parallel sides, a little flattened across the 

 middle of the basal tergite; the pile is scanty, fine, 

 appressed and setate and there is a patch of erect, 

 slender bristles and bristly pile on the sides of the 

 first and second tergites. Males with seven tergites, 

 the seventh tergite a little less than half as long as the 

 sixth. Females with eight tergites, the eighth being 

 more than half as long as the seventh. Male terminalia 

 fully rotate, the epandrium cleft to the base but over- 

 lapping; gonopod short and wide basally. The hy- 

 pandrium is moderately prominent but narrow and 

 broadly rounded apically; it is densely bristly and 

 without any terminal process. The acanthophorites 

 of the females are short and bear a few, short spines. 



As I have been unable to learn of a previous designa- 

 tion, I select Cylicomera rubrofasciata as the type of 

 genus. 



Distribution : Neotropical : Cylicomera fraterna 

 Lynch Arribalzaga (1881) ; rubrofasciata Lynch Ar- 

 ribalzaga (1881). 



Genus Sphageus Loew 



Figures 117, 474, 912, 921, 1576A, 1576B, 1740, 1901, 2051, 2055 



Sphageus Loew, Berliner Ent. Zeitschr., vol. 10, p. 32, 1866. 

 Type of genus : Sphageus chaleoproctus Loew, 1866, by 

 monotypy. 



These flies have strong facial bristles and elongate, 

 slender antenna. The general form is similar to Dizo- 

 nias Loew to which it is closely related, and from which 

 it is distinguished largely through the presence of a 

 cluster of many stout, close-set bristles on the anterior 

 aspect of the middle femur. The third antennal seg- 

 ment lacks the excision present in Dizonias. Length 

 22 mm. 



Head, lateral aspect: The head is comparatively 

 short, the eyes flattened anteriorly. The face is 

 moderately produced, more prominent below, pubescent 

 and convexly arched from the eye margin to the middle. 

 Cheeks developed and visible below the eyes. The 

 occiput is well developed and bears dense, long pile 

 and some moderately stiff bristles on the upper part; 

 these bristles are situated medially and a considerable 

 distance from the eye margin. Proboscis slightly 

 flattened upon the upper half, with dorsal ridge, and 

 nearly two times the length of the head; apex small 

 but rounded and pilose. Palpus clearly of two seg- 

 ments; the first segment is troughlike and excavated 

 and pilose; the second segment is perforate apically 

 and bears numerous, long, bristly hairs. The antenna 

 is elongate and slender and a little longer than the 

 head. The first segment is IV2 times as long as the 

 second segment. The third segment is more than twice 

 the combined length of the first two segments and of 

 uniform width; the apex is dorsolaterally open with a 

 minute, enclosed spine ; no microsegment present. 



Head, anterior aspect : The face is moderately wide 

 and slightly divergent below. It bears down the 

 middle numerous, stiff bristles which begin close to but 

 not quite at the antenna and are restricted to the middle 

 of the face, except at the lower epistomal margin where 

 they spread out laterally, fanlike, in one row. The 

 bristles gradually become longer as they extend down 

 the face so that at the epistomal margin they are as 

 long as the proboscis. The front is pubescent and the 

 sides along the eye margin have a band of pile. Front 

 and vertex slightly wider than the upper face. Ocel- 

 larium with a tuft of pile; vertex shallowly excavated. 



Thorax: The mesonotum has differentiated row of 

 appressed acrostical pile and more abundant lateral 

 pile. Humerus micropubescent and pilose and with 

 3 weak bristles. Laterally the mesonotum has 4 or 5 

 quite strong notopleural, 3 supraalar, 3 or 4 postalar, 

 and 2 rows of weak postdorsocentral bristles. Scutel- 

 lum with 2 pairs of stout, long bristles on the margin 

 and scattered long hair on the disc; the margin is con- 

 vex. Metanotum is micropubescent, bulbous and con- 

 vex with no pile. There is abundant pile on posterior 

 and upper mesopleuron and upper stemopleuron. 

 The propleuron has 4 or 5 medium stout bristles on the 

 convex lateral sclerite and 8 pairs on the pronotal dor- 

 sal collar. There is a subtriangular area of pubescence 

 on the upper stemopleuron and posterior hypopleuron, 

 a similar area on the posterior upper mesopleuron. 

 Metapleuron convex with vertical band of stiff, long 

 hairs or weak bristles. There is some scattered, ap- 

 pressed pile on the middle of the hypopleuron. 



Legs: The hind femur gradually becomes a little 

 stouter distally; it has abundant appressed pile and 4 

 lateral, 2 dorsal subapical, 1 dorsoapical, 3 medioapical 

 bristles, and 1 dorsal subapical bristle; it also has a 

 long, medial row of fine hairs down its entire length. 

 Hind tibia with 5 dorsal, 3 or 4 dorsolateral, 3 ventro- 

 lateral, and 4 or 5 ventromedial bristles; at the apex 

 it bears 1 medial, 3 ventral, 1 dorsal, and 1 lateral 

 bristle. Middle femur with 1 or 2 subapical postero- 

 dorsal bristles. This femur bears a characteristic 

 cluster of numerous, stout, black bristles in the middle 

 anteriorly; this conspicuous mass of bristles separates 

 these flies from its nearest relative which is Dizonias 

 Loew. The anterior femur has 4 clustered, black, ven- 

 tral bristles at the base, 2 lateral apical and 1 or 2 dor- 

 sal subapical bristles. The anterior tibia has a double 

 row of dorsal bristles consisting of 6 or 7 pairs and at 

 the apex 2 posterior, 3 ventral, 2 anterior and 2 dorsal 

 bristles; there is no tibial spine present. 



Wings : The venation as in Dizonias. 



Abdomen: The abdomen is cylindroid with numer- 

 ous, stiff hairs on the sides of the first tergite; no 

 bristles are present on the remaining tergites. Second 

 tergite laterally with long, fine pile; remainder of 

 abdomen with extremely short, fine pile. Female with 

 acanthophorites and lateral spines. 



Distribution : Neotropical : Sphageus chaleoproctus 

 Loew (1866). From Cuba. 



