LAPHRI1NAE 



ROBBER FLIES OF THE WORLD 



397 



black bristle, notopleuron with none. Postalar and 

 scutellum with none. The scutellar disc and prescutel- 

 lar area, the acrostical and dorsocentral areas each 

 bear minute pile which becomes flat appressed in front 

 of the scutellum. Scutellum flat; metanotal slopes 

 with 10 to 12 rather short, very stout, black, bristly 

 spines. Mesopleuron with a large oval area of ap- 

 pressed, short, golden pile; no bristles. Posterior 

 border of mesopleuron and sternopleuron densely, grey- 

 ish yellow pubescent. Hypopleuron with a few long 

 hairs. Metapleuron strongly bulging with a fan of 12 

 long, slender, yellow hairs, bent downward distally. 

 Lateral metasternum with pile; postmetacoxal area 

 short and fully chitinized. 



Legs: The hind femur is distinctly thickened dis- 

 tally. It bears a ventral row of abundant, fine, long, 

 erect, reddish pile; toward the base there are 3 quite 

 long, erect, medial hairs; there are 4 similar hairs near 

 the middle ventrolaterally, with shorter elements to- 

 wards the apex and base; this femur bears 1 stout, 

 short, yellow bristle laterally at the apical fifth, none 

 dorsally. Hind tibia ventrally with similar, erect, red- 

 dish pile and with 2 long, curved, slender, pale, ventral 

 bristles situated at the middle and the outer fourth. 

 There are 2 bristles almost as long, stouter and lateral 

 with an additional shorter bristle near the base; no 

 dorsal bristles present. Middle femur without special 

 bristles. Middle tibia with long, erect, ventral pile 

 and its dorsal surface with 2 long, moderately stout, 

 pale, oblique bristles at the basal and distal thirds; 

 the anterior surface has 1 moderately long, basal 

 bristle ; it also has 2 exceptionally long, ventral bristles. 

 Anterior apex of first two middle tarsi each with a 

 very long, yellow bristle. Anterior femur with a weak, 

 short, dorsal bristle at the apical fourth, 3 long, yel- 

 low haire ventrally on the basal half, and a few shorter, 

 erect hairs. Anterior tibia with several, quite long, 

 slender, anteroventral and posteroventral, bristly hairs, 

 set closely and only slightly divergent; there are 3 

 anterior and 3 posterior bristly hairs with others of a 

 half to a third their length scattered between. Apex 

 with 2 long, anterior bristles. Anterior tarsus with 

 only moderately long bristles. Claws short and sharp ; 

 pulvilli two-thirds as long as claw; the empodium bas- 

 ally thickened. 



Wings : The wings are relatively wide. The marginal 

 cell is closed with an extremely long stalk, the fourth 

 posterior cell closed some distance from the margin, 

 the stalk absent; veins ending discal and fourth pos- 

 terior cell nearly aligned. Anal cell closed with an ex- 

 ceptionally long stalk. The ambient vein ends at the 

 second posterior cell. The second submarginal and first 

 and second posterior cells are elongate, slender, with 

 parallel sides. Alula quite narrow. 



Abdomen: The abdomen is subcylindrical and 

 strongly punctulate, with a slightly purplish reflection. 

 The first tergite is nearly as long as the second; the 

 second tergite is slightly wider and almost if not quite 

 as wide as thorax. The dorsal pile is microscopically 

 short, set in punctures. Sides of the first tergite with 



4 quite short, stout, blackish bristles; remaining ter- 

 gites without bristles and lateral pile extremely short 

 but the posterolateral margin near the sides has a nar- 

 row, short band of silvery pubescence on the second 

 to fifth segments. Only six tergites are visible, the 

 last is as long as the fifth, but very strongly cupped, 

 especially apically so that the small but inconspicuous 

 terminalia are enclosed dorsally and laterally and vis- 

 ible only from below. The seventh tergite is a short 

 shield appressed against the internal surface of the 

 sixth and not extending beyond it. 



Distribution : Neotropical : Cyphotomyia lynchii Wil- 

 liston (1889). 



Genus Opocapsis Hull 



Figures 258, 6G2, 1350, 1359, 1570 



Opocapsis Hull, Proc. Bnt. Soc. Washington, vol. 60, p. 252, 1958. 

 Type of genus: Lnphria dioctroides Walker, 1860, by orig- 

 inal designation. 



Quite small, slender flies, immediately recognized by 

 the complete absence of one of the posterior cells, which 

 may be assumed to be the third posterior cell, and of 

 which there is no trace. The face is quite narrowed, 

 with 2 fine bristles above, 2 somewhat longer ones 

 below. The proboscis is minute, cylindrical apically 

 but from the dorsal aspect rather strongly swollen; it 

 barely protrudes beyond the face and is not constricted 

 in the middle. The hind femur is rather strongly 

 dilated from the base, widest across the apical third. 

 It is related to Clariola Kertesz and separated by the 

 reduced number of posterior cells. Length 5 or 6 mm. 



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

 eye, except for a minute elevation on the lower sixth 

 of the head. The upper occiput has a single, short, 

 stout, black bristle on each side. The proboscis is small 

 and extremely short, scarcely protruding beyond the 

 face ; unconstrieted, from the dorsal aspect it is swollen. 

 The palpus is extremely minute and slender and wedged 

 in between the inner margin of the eye and the sides 

 of the proboscis. There appears to be two segments, the 

 basal one exceptionally minute and short, and with 3 

 or 4 fine, minute hairs on its free ventral and lateral 

 surfaces. Second segment long and slender without 

 evident pile though there seems to be some minute pu- 

 bescense. The antenna is attached at the upper fifth 

 of the head, the first segment slender and elongate, more 

 narrow than the second and twice as long; it bears a 

 pair of long slender bristles in the middle ventrally. 

 Third segment longer than the first two segments com- 

 bined and tapered from the base to a coniparat ively fine 

 point at the apex; in the middle of the dorsal margin 

 it has a deep incision with basal bristle. 



Head, anterior aspect: The face below the antenna 

 is a seventh the head width and barely divergent below 

 at the epistoma. The face bears coarse, erect pubescence 

 and a vertical row of 5 or G appressed, somewhat 

 matted, scaliform, shiny hairs. The lateral margin of 

 the remainder of the face has a linear row of shining 



