LAPHRIINAE 



ROBBER FLIES OF THE WORLD 



415 



the first two segments bear exceedingly long, stout 

 bristles, nearly equal in length to the first three seg- 

 ments; tarsi end in well developed pulvilli, empodium, 

 and sharp claws. 



Wings: The marginal cell closed with a long stalk; 

 the anterior branch of the third vein ends barely above 

 the apex, the posterior branch well behind. Second 

 posterior cell widely open or slightly narrowed; fourth 

 posterior cell closed and stalked and ending beyond the 

 discal cell; the discal cell therefore has one end vein. 

 Anal cell closed; second basal cell closed with three 

 veins; alula narrow, ambient vein ends at the end of 

 the second posterior cell. 



Abdomen : The abdomen is as wide as the mesonotum 

 and with nearly parallel sides ; the tergites are slightly 

 convex, coarsely and thickly punctulate; the first seg- 

 ment is unswollen laterally. Pile of abdomen short, 

 appressed setate, a little longer along the lateral mar- 

 gins, the sternites with short appressed pile; weak 

 bristles are present on most of the tergites, the first ter- 

 gite bears 3 pairs of bristles, relatively stout ; the second 

 has a single, stout bristle in the middle of the lateral 

 margin ; remaining tergites with only stiff hairs. Male 

 terminalia similar in general plan to Atomosia Mac- 

 quart. The encircling arms of the gonopod turn sharply 

 backward to form an adjacent pair of toothlike struc- 

 tures. Female terminalia very short and minute and 

 recessed in the cuplike sixth tergite, the seventh tergite 

 forming a linear rim at the apex of the sixth ; they have 

 a medial dorsal fissure. 



Distribution: Nearctic: Atoniomyia duncani Wilcox 

 (1937). 



Neotropical: Atoniomyia albiceps Hermann (1912) ; 

 ancylocera Schiner (1868); bigoti Bellardi (1861); 

 brevistylata Williston (1901) ;fulvipes Carrera (1946) ; 

 grossa Carrera (1946) ; hispidella Hermann (1912) ; 

 latere punctata Hermann (1912) ; mikii Williston 

 (1886) ; mollis Hermann (1912) ; pinguis Hermann 

 (1912) ; scalarata Hermann (1912) ; setigera Hermann 

 (1912) ; viduata Wiedemann (1819). 



Genus Dissmeryngodes Hermann 



Figubes 260, 659, 1330, 1339, 1571, 2125 



Dissmeryngodes Hermann, Nova Acta Acad. Caes. Leop.-Carol., 

 vol. 96, p. 75, 1912. Type of genus: Laphria antica Wiede- 

 mann, 1S28, by original designation. 



Rather small flies; the abdomen tends to be some- 

 what elongate, thickened posteriorly, clue to the sides 

 being downturned. They will be rather easily recog- 

 nized by the quite narrow face, the small, short, cylin- 

 drical proboscis, the long, slender antenna which car- 

 ries a conspicuous apical microsegment and above the 

 point of its attachment a bristly spine. Finally, the 

 end vein of the discal cell and the fourth posterior cell 

 are nearly or quite aligned; and especially should be 

 noted the somewhat thickened, hind femur which bears 

 4 ventrolateral, distal, stout, tuberculate spines. Length 

 9 to 11mm. 



Head, lateral aspect: The face is plane with the eye 

 margin, slightly produced on the lower fourth, due 

 only to the gentle recession of the eye. The eye is 

 high, distinctly narrowed below. The eyes rather 

 strongly flattened medially in front, Occiput moder- 

 ately developed, but on the whole rather short; it is 

 obliterated dorsally and recedes also vent rally but 

 closer to the bottom of the eye. Pile of the occiput 

 rather fine and short, the bristles begin above the 

 middle of the head, where there are 1 or 2 slender, 

 pale bristles followed by 6 or 7 dorsal pairs of straight, 

 exceptionally stout, strongly attenuate, and pointed, and 

 conspicuous bristles. The deeply placed medial pair 

 cross each other. Proboscis small, short, subcylindri- 

 cal, a little swollen on the basal half and directed 

 obliquely downward in some specimens and, in others 

 horizontally forward ; the latter seems to be the char- 

 acteristic position. The proboscis is no longer than 

 the face, truncate apically with a short, bristly, quite 

 apical fringe and 4 or 5 bristly hairs ventrally at the 

 base. Palpus minute, short, cylindrical with apical 

 bristle. 



Antenna attached at the upper fourth of the head, 

 rather long and comparatively slender; the third seg- 

 ment is sometimes rather widened and rather strongly 

 compressed laterally ; in other cases it is more narrow 

 and progressively narrowed towards the apex. This 

 segment is 2V& times the combined length of the first 

 two segments and in any case bears a conspicuous, long. 

 pubescent, ventromedial microsegment ; and attached to 

 the third segment dorsally at the base of the microseg- 

 ment is a bristly, basally swollen spine; the microseg- 

 ment is a seventh the length of the third segment. 

 First antennal segment with abundant, bristly setae 

 ventrally and in the middle below with a single, long, 

 stout bristle; second segment with 1 or 2 rather long, 

 slender bristles dorsally, 1 or 2 short, bristly setae and 

 7 or 8 ventrally. Third segment very slightly concave 

 at the base dorsally. 



Head, anterior aspect : The head is only a little wider 

 than high. The antenna is only a sixth the head width 

 or less and at the epistoma scarcely wider. Subepisto- 

 mal area small, bare, nearly plane, slightly oblique. 

 The face is micropubescent, with 3 or 4 long, slender, 

 bristly hairs on the dorsal half, often pale, strongly 

 curled downward and with some shorter, fine pile. 

 Lateral subepistomal margin with 1 to 3 pairs of long, 

 slender bristles. Front quite short, with 2 slender 

 bristles along the eye margin ; the vertex is deeply ex- 

 cavated, with sloping sides, the upper corners but little 

 excavated; the ocellarium is rather large, high, with 

 steep sides, narrow at the top and steep behind; it 

 bears a pair of long, moderately stout bristles and a 

 pair of minute, hairs behind. Anterior eye facets 

 strongly enlarged. 



Thorax: The pleuron appressed pubescent, except 

 over the greater dorsal middle portion of the mesopleu- 

 ron. Mesonotum and humerus bare, except narrowly 

 along the margin. Pile of mesonotum rather scanty 

 but bristly and appressed or suberect; it is nearly erect 



535914 — 62— pt. 1- 



-28 



