DASTPOGONINAB 



ROBBER FLIES OF THE WORLD 



199 



Sintoria emeralda, new species 



A species rather readily recognized by the dark blue- 

 green reflection on the sides of the mesonotum and the 

 bottle-green color of the abdomen in the male, and on 

 the sides of the female abdomen; middle of female 

 abdomen tends to be more violaceous. Length 9 mm. 



Male. Head : The head is black with thin, greyish or 

 brownish yellow pollen or micropubescence on the front 

 and face, which does not obscure the ground color or the 

 slightly greenish reflection. Pile and bristly hairs of 

 the face light yellow. Antenna black with the bristly 

 hairs dark reddish brown. The pollen of the third seg- 

 ment reddish brown. 



Thorax: The thorax is shining bluish to greenish 

 black with pale brownish yellow pollen and micropubes- 

 cence and pile of the same color, which, however, be- 

 comes somewhat reddish down the middle of the 

 mesonotum and quite golden on the posterior part of 

 the mesonotum. All this posterior part of the mesono- 

 tum and most of the lateral mesonotum, except the mar- 

 gin, is bare and sliining. 



Legs: The legs everywhere metallic, shining green 

 or greenish black. The pile and bristles uniformly 

 brownish yellow. 



Wings : The wings are distinctly tinged with brown, 

 but not at all dark in color. Anterior veins light red- 

 dish brown, other veins darker. 



Abdomen : The abdomen in the male is shining green 

 with greyish white pubescence in the posterior and 

 lateral corners. Female with abdomen becoming more 

 or less coppery or violaceous in the middle but green 

 laterally. Posterior spines of female dark red. Pile 

 of both sexes pale yellow to whitish. 



Type: Male, Nepantla, Mexico, October 28, 1923, 

 E. G. Smith; allotype, female, La Cascada, Mexico, 

 October 28, 1922, E. G. Smith. In the U.S. National 

 Museum. 



Genus Itolia Wilcox 



Figubes 70, 593, 989, 998, 1832, 1833, 1954 



Itolia Wilcox, Pan-Pacific Ent, vol. 12, p. 201, 1936. Type of ge- 

 nus : Itolia maculata Wilcox, 1936, by original designation. 



Small flies at once characterized by the reduction of 

 the posterior cells to four, the bare, partly pollinose, 

 partly shining aspect and the rather humped appear- 

 ance of the mesonotum. Head longer below than 

 above, the anterior eye facets unusually large. Length 

 4 to 8 mm. 



Head, lateral aspect: The head is short, especially 

 above, the length greater below and accentuated by 

 the more prominent ventral development of the occiput. 

 The occiput rapidly rises at the eye margin to reach its 

 maximum thickness near the eye. Face quite short 

 and barely visible in profile even below. Pile of occiput 

 fine, weak bristles are present submarginally, beginning 

 near the middle of the head. The proboscis is small, 

 cylindroid, bluntly pointed, tapered only at the imme- 



diate apex, and does not extend beyond the face. 

 Palpus of two segments, but small and inconspicuous; 

 the second segment is slender, cylindrical, with apically 

 directed tuft of bristles at the apex. The antenna is 

 attached a little above the middle of the head and 

 approximately as long as the head or a little shorter. 

 First and second segments short, subequal. The third 

 segment is 2y 2 to 3 times as long as the combined length 

 of the first two, gently attenuate from its base and 

 bearing two microsegments, the first microsegment 

 small, the second several times longer with a distinct 

 apical spine. First and second segments bear weak 

 bristles ventrally at the apex. 



Head, anterior aspect: The head is wide, flattened 

 anteriorly, considerably wider than the thorax. The 

 face below antenna is about one-fifth the head width, 

 sometimes a little more or a little less. The face below 

 and the front above is slightly divergent. The face 

 appears to be pubescent, but is densely covered with 

 short, flat appressed, slightly flattened, silvery pile. 

 Bristles and longer pile are restricted to the epistomal 

 margin where there is a narrow band extending diag- 

 onally downward, somewhat tectiform, above the pro- 

 boscis, and matching the color of the pubescence. 

 Front is flat, clothed like the face, without long pile 

 or bristles. The ocellarium is prominent with nearly 

 vertical sides and several short hairs between the ocelli. 

 The anterior ocellus greatly enlarged. 



Thorax: The mesonotum is comparatively high and 

 strongly arched posteriorly and more so anteriorly. 

 Generally there is a medial stripe and a large triangular 

 area laterally which is polished and bare; small areas 

 of the pleuron are similar. All the remainder of the 

 thorax is densely, coarsely, appressed pubescent with 

 pile restricted to a few fine, scattered hail's. An acros- 

 tical row of bristles is present and dorsocentral bristles 

 though weak are differentiated at a point a short dis- 

 tance behind the humerus. All the lateral bristles are 

 quite weak, and consist of no humeral, 2 notopleural, 

 1 or 2 supraalar, 1 or 2 postalar, and no scutellar 

 bristles. Scutellar margin with or without a few weak 

 hairs, the disc bare. Propleuron with abundant, weak 

 pile; the entire dorsal surface and posterior half of the 

 mesopleuron, the lateral and ventral metasternum with 

 abundant, long, fine pile. Metapleuron with a vertical 

 band of numerous, fine, apically crinkled hairs. Meta- 

 notum with micropubescence only. Some of these ele- 

 ments and some of those on the mesopleuron might be 

 regarded as weak bristles. Postmetacoxal area mem- 

 branous. Presternum dissociated. 



Legs: The femora are moderately stout without be- 

 ing swollen; they bear fine, appressed pile; the ventral 

 surface, especially on the hind pair has a fringe of 

 erect, fine pile and several much longer, slender hairs. 

 Bristles absent. Tibiae with similar pile and very weak 

 bristles. The posterior tibia has 5 or 6 such elements 

 ventrolaterally. Middle tibia with short bristles pos- 

 terodorsally, 4 rather long, attenuate, anterodorsal 

 bristles and 3 or 4 long, ventral bristles. The postero- 

 ventral bristles of the anterior tibia are lonff but slen- 



