DASYPOGONINAB 



ROBBER FLIES OF THE WORLD 



143 



Distribution : Neotropical : Dicranus jaliscoensis Wil- 

 liston (1901); rutilus Wiedemann (1821); schrottlcyi 

 Bezzi (1910) [=Io?igiunguhttus Macquart (1S49), not 

 Macquart (1838)]; nigerrima Carrera (1955); tucma 

 Lynch Arribalzaga (1880). 



Bezzi (1910c) changed the name of Dasypogon long'i- 

 ungulatus Macquart, 1849, to Dicranus schrottkyi, new 

 name, on account of prior use of the name longiungu- 

 latus by Macquart (1838) in Dasypogon. Since the 

 longiungulatus Macquart (1849) is a Dicranus, and 

 longiungulatus Macquart (1838) is said to be a syno- 

 nym of Allopogon vittatus Wiedemann (1828), I be- 

 lieve that further study will show that this is an 

 unnecessary change of name. 



Alyssomyia, new genus 

 Figures 154, 480, 1013, 1022, 1S30 



Type of genus : Uypenetes brevicornis Philippi, 1865. 



Small, cylindroid, short pilose flies; the wings much 

 shorter than the abdomen. Face distinctly and clearly 

 plane, nowhere convex. Mesonotum with long, dor- 

 socentral bristles beginning anteriorly. While the 

 third antennal segment is not sharply contracted or 

 narrowed at the base, these flies are probably related to 

 Hypenetes Loew. They are readily separated from 

 Zaorotica Hull by the plane face. Length 11 mm. 



Head, lateral aspect : Length of head is normal. The 

 face is nearly straight vertically and is visible only on 

 the lower two-thirds, where because of the narrowing 

 of the eye it is a little more conspicuous. Occiput 

 moderately prominent in the middle, more so below 

 and obliterated near the vertex. The occipital pile is 

 scanty, stiff, moderately long and scattered over the 

 medial area but becomes sublateral to the eye margins 

 ventrally where it is longer, opaque white and more 

 abundant. Bristles begin at the lower third of the occi- 

 put, are distinct but not stout, and consist of 17 pairs 

 of white bristles slightly curved forward. The pro- 

 boscis is short, slightly expanded basally from either 

 view with a low, dorsomedial ridge ; the apex is strongly 

 tapered from the upper surface to a moderately sharp 

 point. The apex bears fine pile; base below with some 

 long hairs. Palpus of two segments; first, segment 

 excavated, second segment microporate sublaterally ; 

 pile scanty but long. The antenna is attached to the 

 upper third, is rather short, the first two segments nearly 

 equal in length with the first slightly longer; the sec- 

 ond sesrment is beadlike. The third segment is later- 

 ally flattened and gradually expanded from the base 

 until at the outer third it is more than twice as high as 

 at the base; it is then rapidly attenuate from below to 

 its apex which bears a short, thick, oblique microsub- 

 segment to which is attached a short, stout, distinct 

 spine. First segment with 3 to 4 rather long, stout, 

 white bristles below, 2 shorter elements laterally ; second 

 segment with 2 long, stout bristles ventrally. 



Head, anterior aspect : The face below antenna is one- 

 fourth the head width and slightly divergent below. 



Face pubescent, without pile, but with a rather dense, 

 vertical band of stout, moderately long, pale, or black- 

 ish bristles on either side of the midline, which extends 

 upward slightly more than half the length of the face. 

 Each group contains about 12 bristles. In addition the 

 epistomal margin bears at least 12 pairs of still longer, 

 stout, white or sometimes dark bristles. Subepistomal 

 area short, nearly horizontal and concave. The front 

 is narrowly divergent above the antenna and the vertex 

 of practically the same width as the upper front. Sides 

 of front with a single row of 8 moderately stout bristles. 

 Ocellar protuberance low with 5 pairs of white bristle?. 

 Anterior eye facets strongly enlarged and zoned. 



Thorax: The mesonotum is pollinose laterally, the 

 pleuron also pollinose. The mesonotal pile is very 

 scanty, appressed, stiff, pale setate; it is almost bristly 

 and is restricted to patches; there is a band bordering 

 the humerus medially and posteriorly, a patch above 

 the whig, a patch in front of the scutellum, a single row 

 of acrostical bristles anteriorly, instead of pile. Dor- 

 socentral elements consist of 7 stout bristles in each row, 

 2 of them opposite the humerus, 2 opposite the noto- 

 pleural area. Humerus pilose and with 5 pale bristles; 

 lateral bristles long and stout and chiefly pale. There 

 are 3 notopleural bristles in an oblique row, 1 postsu- 

 praalar, 2 postalar, and 3 pairs of bristles on the scutel- 

 lum. Scutellum moderately thick with flat disc, 

 pubescent only. Pleuron with scattered, long hairs, 

 which are quite stiff, the pronotum with 7 or 8 pairs of 

 weak, white bristles. Upper margin of mesopleuron 

 with a few short, thick hairs; posterior margin and 

 anterior extension with a cluster of dense, mostly flat, 

 appressed, thick, white pile. Upper sternopleuron with 

 11 similar hairs. Upper anterior pteropleuron and 

 posterior hypopleuron with a cluster, the latter without 

 a differentiated patch spot of micropubescence. Meta- 

 pleuron with a vertical band containing 7 or 8 stout, 

 rather long, pale bristles. Metanotal slopes pubescent 

 only; metasternal slopes with 10 to 12 fine hairs. 

 Metasternum with 4 or 5 hairs on each side. Post- 

 metacoxal area membranous; tegula pubescent only. 



Lens: All the femora are distinctly though moder- 

 ately thickened. All pile and bristles pale, the pile flat 

 appressed, the bristles stout but of moderate length, 

 mostly oblique. The hind femur bears a transverse row 

 of 3 apical bristles, which tend to be medial rather than 

 dorsal. There is a single subapical dorsal, 4 dorso- 

 lateral, 4 lateral, 5 ventrolateral, and 7 ventromedial, 

 which are slightly longer. Hind tibia bears 4 dorsal, 4 

 lateral, 3 ventral bristles and its apex has 1 dorsal, 2 

 medial, 1 lateral, and 3 ventral bristles. Hind basitarsus 

 considerably shorter than the remaining tarsi. Middle 

 femur with 3 dorsoposterior bristles near the apex, 1 

 anterior subapical and 1 near the base, and 5 or 6 pos- 

 teroventral elements. This tibia has 4 posterodorsal 

 and 5 anterodorsal bristles, the middle two of which are 

 much longer and stouter. Ventrally there are 4 bristles, 

 the basal 2 slender, the middle and outer element stout 

 and long. The apical circlet contains 9 bristles. An- 

 terior femur with 4 dorsal and near the outer third 1 



