Dolichopodidae. 189 



12. H. chalybeus Wied. 



1817. Wied. Zool. Mag. I, 72, 18 (Dolichopus). — 1831. Stann. Isis 

 1831, 142, 35 (Dolichojms). — 1842. Stæg. Krøyer's Tidsskr. IV, 37, 31 

 (Dolichopus). — 1843. Zett. Dipt. Scand. II, 580,69 (Dolichopus). — 1862. 

 Schin. F. A. I, 210. — 1903. Kat. palåarkt. Dipt. II, 317. 



Male. Vertex and frons blue. Epistoma somewhat broad, greyish 

 white. Palpi yellowish. Occiput bluish black, greyish pruinose; post- 

 ocular bristles black. Antennæ scarcely as long as the head, black, 

 the first joint yellow below ; third joint short triangular, not as long 

 as broad; arista distinctly hairy. Thorax dark steel-blue, slightly 

 pruinose, shining; scutellum very short-haired, at the margin the hairs 

 longer. Pleura greenish, grey pruinose; propleura with a few pale 

 hairs and a black prothoracic bristle. Abdomen dark greenish or 

 more æneous, sometimes with coppery reflexes, distinctly whitish 

 pruinose downwards; it is clothed with short, black hairs, and has 

 somewhat long hindmarginal bristles, which are not longer on the 

 first segment. Venter greenish, greyish pruinose, with short, dark 

 hairs. Hypopygium mainly constructed as in the other species, but 

 however with some differences; it is rather slender, the ventral lobes 

 issue longer backwards, they are shorter and more dilated at the 

 apex, and have here some hairs; the inner lamellæ are longer, and 

 curved towards each other; the outer lamellæ are not small, of oval 

 shape; they are yellowish white with a black margin; the outer half 

 of the dorsal margin has longish teeth with strongly curved hairs, the 

 apical and ventral margin are serrated, and have very long, fme hairs, 

 shorter on the inner part of the ventral margin. Legs yellow, front 

 coxæ a little darkened at the base, posterior coxæ grey with the apex 

 yellow; hind femora a little brownish above at the apex, hind tibiæ 

 more or less brownish, becoming blackish towards the apex; anterior 

 tarsi with the apex of metatarsus and the following joints black or 

 brownish black, hind tarsi black; the hind metatarsus a little shorter 

 than the second joint. The legs have short, black hairs, paler below 

 the anterior femora; hind femora with one preapical bristle; front 

 tibiæ with some bristles above, and one on the postero-ventral side; 

 middle tibiæ with two rows of bristles above, and with two antero- 

 ventral bristles; hind tibiæ with two dorsal and one ventral row of 

 bristles. Wings somewhat strongly brownish tinged, most towards 

 the anterior margin, the extreme base clear; veins black or brownish 

 black; the discai vein almost not bent, slightly converging towards 

 the cubital vein; axillary lobe very small. Squamulæ yellow, with a 

 black fringe. Halteres yellow. 



