DASVPOGONINAE 



ROBBER FLIES OF THE WORLD 



279 



poorly developed in profile, with scattered, coarse hairs 

 below and below the middle of the head slender bristles 

 which never become stout and are continued mostly in 

 a row to the vertex. Behind the vertex there is a patch 

 of 3 bristles on each side. Proboscis moderately long 

 and slender, with unusually high dorsal ridge and dor- 

 sally arched down to a comparatively sharp point. 

 Palpus of two segments, the first excavated, the second 

 clublike with an apical pore and many bristly hairs. 

 The antenna is attached at the upper fifth of the head 

 or higher and not greatly below the vertex ; the eye rises 

 above the vertex. The first segment is slightly longer 

 than the second, about 2y 2 tunes as long as wide, the 

 second segment at least twice as long as wide, or longer, 

 both with unusually stubby setae located almost entirely 

 laterally and dorsally. The first segment has a basi- 

 lateral bristle ; the third segment is not quite twice the 

 combined length of the first tw T o segments ; it is a little 

 widened towards the middle, attenuate distally, and 

 ends in a transverse subcircular opening in which is 

 located a short, stout spine. 



Head, anterior aspect: The head is nearly twice as 

 wide as high, the upper face about one-fourth the head 

 width, slightly wider below. The face cover consists 

 of very fine pubescence without pile. The mystax con- 

 sists of 3 pairs of very stout, moderately long bristles. 

 Subepistoma large, oblique, concave. Front large, shal- 

 lowly concave, partly pollinose, with 3 or 4 unusually 

 stout bristles along the ocular margin; 1 or 2 others 

 and a patch of bristly setae on the sides of the vertex. 

 Vertex very little excavated, slightly narrow ; the ocel- 

 larium is small but high, with steep sides and between 

 the ocelli 2 pairs of stout, anteriorly curved bristles. 

 Front wider than upper face. 



Thorax : The thorax is moderately high, the meso- 

 notum comparatively high and gently convex, abrupt 

 at each end and covered with very scanty, scattered, 

 stout setae. There is a bare middle stripe with an 

 acrostical row of setae. Near the middle begin rows 

 of dorsocentral setae and in these rows are 2 or 3 stout, 

 long, posterior bristles. Lateral bristles conspicuously 

 stout and long. There are 2 anterior humeral bristles, 



2 notopleural, 2 supraalar, 2 on the postalar callosity, 

 and 1 pair on the flat scutellum. The metanotum is 

 moderately large, the callosity with pubescence only. 

 Halteres large. Pleuron largely bare except for pollen. 

 Pronotum with quite long, slender bristles. Lateral 

 propleuron with 2 stout bristles. Metapleuron with 



3 or 4 very slender bristles and a few hairs. Postmeta- 

 coxal area membranous ; only the lateral metasternum 

 with pile; presternum fully dissociated. 



Legs: The legs are moderately long and compara- 

 tively slender, the hind femur perhaps a little more 

 stout and narrowed at the immediate base. The femora 

 and tibia bear moderately abundant but rather scat- 

 tered, evenly distributed, sharply appressed setae. 

 Hind femur with a very weak, small bristle at the 

 apex ventromedially and no others. Hind tibia with 

 stout, rather short bristles, 4 dorsolateral, 3 dorsome- 

 dial, 4 longer ventrolateral, and ranked setae medially 



535914 — 62— pt. 1 19 



on the distal half; apex with 6 bristles. All tarsi 

 slender; first tarsal segment as long as the next 3 seg- 

 ments. Middle femur with a stout, posterodorsal, 

 apical bristle and a quite basal, ventral bristle. Ante- 

 rior femur only with a weak, apical, posterodorsal 

 bristle. Middle tibia with 3 anterodorsal, the last one 

 long, spikelike and distal ; on it are 3 minute, postero- 

 dorsal, 3 similar posteroventral bristles, and 2 very 

 conspicuous, long, stout, ventral bristles. Anterior 

 tibia with 3 small anterodorsal, 5 minute posterodorsal, 

 4 similar posteroventral, and 2 long, stout, ventral bris- 

 tles. Apex of its tibia with a short protuberance and 

 a very stout, strongly bent but not twisted spine ap- 

 posed to a basitarsal swelling with many denticles. 

 Claws long, sharp; pulvilli well developed; empodium 

 swollen at the base. 



Wings: The wings are tinged with brown along the 

 veins. Marginal cell open by less than its maximal 

 width, the basal expansion of the second submarginal 

 cell is wholly in front of the third vein. Posterior 

 cell widely open, anal cell quite widely open; alula 

 large ; ambient vein complete. Wing distally is wholly 

 villose. The upper section of the anterior intercalary 

 vein is nearly as long as the medial crossvein. Pos- 

 terior crossvein reduced or absent. 



Abdomen : Only the first segment of the abdomen 

 is as wide as the mesonotum. This segment is com- 

 paratively long with the metathorax greatly reduced. 

 Surface cover consists of quite scanty, minute, flat ap- 

 pressed setae, a few long hairs on the sides of the first 

 segment only and this segment laterally has a row of 6 

 spikelike bristles. Females with eight segments, the 

 last segment at most is only half as long as the seventh. 

 Female terminalia with acanthophorites and 6 pairs of 

 bluntly rounded, spoonlike spines. Eighth sternite 

 thin, troughlike, but not indented or impressed; the 

 apex is plane and not cleft. 



Distribution : Neotropical : Aczelia argentinm Wulp 

 (1882) ; infumatus Lynch Arribalzaga (1880). 



Genus Archilaphria Enderlein 



Figuees 528, 1129, 1138 



Archilaphria Enderlein, Wiener Ent. Zeitung, vol. 33, p. 151, 

 1914. Type of genus: Archilaphria ava Enderlein, 1914, 

 by original designation. 



Small, more or less hump-backed flies with decum- 

 bent abdomen. The marginal cell, all posterior cells and 

 the anal cell are quite widely open. Proboscis quite 

 short. The face is short, with 1 row of bristles on the 

 mystax. The apex of the anterior tibia bears a distinct, 

 slender, transversely bent, black spine. The genus is 

 allied to Saropogon Loew; the third antennal segment 

 ends bluntly without any microsegment or spine. The 

 femora are stout but not swollen and lack bristles. 

 Tibial bristles, however, are stout. Mesonotal bristles 

 are almost absent. Length 10 to 12 mm. 



Head, lateral aspect: The head is short, strongly 

 flattened in the front ; the face is quite short through- 



