568 



ITNITED STATES NATIONAL MUSEXJM BULLETIN 224 



cens Villeneuve (1912) ; femoratellus Loew (1871) ; 

 fuse! pennis Meigen (1820) [=spinigerZeUer (1840)]; 

 hamulatus Loew (1854) [ = quadriaplculafiis Strobl 

 (1909), rotuJmis Pandelle (1905)]; harpagonis Seguy 

 (1929) ; harpax Villeneuve (1904) [=falcularis Pan- 

 delle (1905)]; hiulcus Pandelle (1905); macropterus 

 Loew (1854) ; obtusnis Becker (1923) ; periscelis Mac- 

 quart (1849); picipes Meigen (1820) [ = 'b'mnnicosus 

 Becker (1923), cinereus De Geer (1776), fforcipatus 

 Linne (1758), jorcipula Zeller (1840), mixtus Loew 

 (1840), peridulus Becker (1923), plehejus Meigen 

 (1820)]; poecilus Becker (1923); praemorsus Loew 

 (1854) \_ = foliiformis Becker (1923), fnigripennis 

 Macquart (1826), tridcns Egger (1855)]; putoni Se- 

 guy (1927) ; rectus Becker (1923) ; setiger Loew 

 (1848); setipyga Becker (1923); stenogastrus Loew 

 (1871) ; styUfer Loew (1854) ; fheodori Engel (1930) 

 \^ = alhociliatus Becker (1907)] ; tricuspis Loew (1848) 

 \_=kervlUei Villeneuve (1910)]; trigonus Meigen 

 (1804) \_ = aTbipilus Meigen (1830), hispidus Zeller 

 (1840), pullm Meigen (1830), spurius Loew (1871)] ; 

 triloius Strobl (1898) ; verticillatus Becker (1907). 



Dufour (1850), Lundbeck (1908), and de Meijere 

 (1916) discuss or describe immature stages of Dysma- 

 chus species. Melin (1923) illustrates stages of Dys- 

 machus picipes Meigen as jorcipula Zeller. 



Lestophonax, new genua 

 FiQUBES 336, 783, 1549, 1558, 2218, 2498, 2499 



Type of genus: Lestophonax mallophoroides, new 

 species. 



Robust flies characterized by the numerous, long bris- 

 tles on the scutellar margin and disc; the prominent 

 face has an abrupt dorsal ledge and the gibbosity bears 

 copious, slender bristles; the antennal style is short 

 and thei'e are numerous, long, slender bristles or bristly 

 hairs on the front and mesonotum. Legs rather densely 

 long pilose. Length 15 mm. 



Head, lateral aspect : The head is comparatively long, 

 if the extensive face is mcluded. The face is ex- 

 tensively produced on the lower three-fourths with 

 dorsally, an abrupt ledge, above which lies a short, 

 steep concavity plane with the eye and bordered above, 

 beneath the antemia, by a moderately short extension 

 of the face. The gibbous portion of the face is con- 

 vex, with the sides quite steep and the cheeks prominent 

 below. Occiput rather thick dorsally, still more prom- 

 inent below due to the marked anteroventral reces- 

 sion of the eye on the lower third of the eye. Lower 

 pile dense, coarse and long. Bristles begin at the mid- 

 dle of the head and include 4 or 5 especially stout bris- 

 tles behind the upper eye corner and also deep-set, 

 dorsal pile. Proboscis of medium width, blunt at apex, 

 with fine, apical pile and distinct preapical crease. 

 Ventrally the basal half bears numerous, long, coarse 

 hairs. Palpus cylindrical, elongate, with many slender 

 bristles. The antenna is attached a little above the 

 middle of the eye ; the first segment is more than twice 



as long as wide and nearly I14 times longer than the 

 second segment. The first and second segments bear 

 long, slender bristles dorsally with similar bristles ven- 

 trally on the second segment and numerous, still longer, 

 equally slender bristles on the lower surface of the sec- 

 ond segment. Third segment I14 times the combined 

 length of the basal segment. At its widest point in the 

 middle, the third segment almost equal in width to 

 the second segment. It is a little narrowed at base and 

 apex. Dorsally it has 3 or 4 fine setae and at the 

 apex a very short microsegment followed by a short, 

 stout, bristle-tipped style only about half as long as 

 the third segment. 



Head, anterior aspect : The width of the head is about 

 1% the height of the eye. Face below antenna less than 

 a fifth the head width and rather strongly widened 

 below. Face surface covered with dense, appressed 

 micropubescence. Beginning at the upper part of the 

 gibbosity is a broad, medial band of numerous, long, 

 quite fine bristles ; this band becomes wider below and 

 extends densely down the whole sides of the subepis- 

 toma. Face beneath antenna without pile. Front dis- 

 tinctly wider than the ui^per face, the vertex narrowed. 

 The front is opaque, black pollinose with several rows 

 of numerous, quite long, bristly hairs occupying the 

 whole lateral fourth along the eye margin. Vertex 

 moderately excavated, with steep sides ; the large ocel- 

 larium low and bears 3 pairs of long, bristly hairs 

 between the ocelli and 4 pairs behind the ocelli. Simi- 

 lar, equally long hairs are clustered in a patch on each 

 side behind the vertex. 



Thorax : The mesonotimi is moderately high and con- 

 vex posteriorly and more abruptly convex anteriorly. 

 It is pollinose and bears numerous, quite long, fine, 

 bristly hairs. There is a double acrostical row of such 

 hairs. The dorsocentral elements become differentiated 

 shortly in front of the suture and are exceptionally long 

 but nowhere form more than very slender bristles. 

 Lateral bristles are even longer and most of them quite 

 slender. There are 2 moderately stout, notopleural, ele- 

 ments, 3 quite slender supraalar, 4 or 5 slender bristles 

 on the postalar callosity. The scutellum has 6 pairs 

 of moderately stout, very long bristles with an addi- 

 tional row of similar bristles across the disc and other 

 scattered, long, fine hairs. Scutellum moderately thick, 

 convex, with distinct impressed rim. Metanotal cal- 

 losity with copious, coarse pile. Pleuron pollinose with 

 long, slender bristles or bristly hairs on the upper 

 sternopleuron, a conspicuous patch of similar, equally 

 long elements on the pteropleuron ; also there are 

 equally long, perhaps more slender elements abundant 

 over the dorsal mesopleuron. Pronotum with dense 

 pile and at most 1 or 2 very weak bristles. Metapleuron 

 with a large, oval patch of exceptionally long and very 

 slender bristles and bristly hairs. Hypopleuron with 

 similar but fewer elements. Postmetacoxal area mem- 

 branous; prosternum dissociated. 



Legs : The femora are all stout with only the anterior 

 and middle femora sliglitly swollen. They are curious 

 because of the abundant, very long, coarse hairs which 



