188 Orthorrhapha brachycera. 



Occiput black, somewhat shining, with black, below with pale hairs. 

 Antennæ black, the third joint rather elongated, the style together 

 with the bristly part short, scarcely half as long as the third joint. 

 Thorax dark æneous, brightly shining. The dorsocentral and acrosti- 

 chal bristles somewhat short, black, the former a little longer behind, 

 and the hindmost long and strong. Fiirther a humeral bristle, a pair 

 of posthumeral, about three notopleural, a supraalar and a postalar 

 bristle, all somewhat long, black. Scutellum with four black marginal 

 bristles. Pleura black, shining, Abdomen black, velvet along the 

 dorsum, but somewhat metallic shining at the sides and on the 

 venter; it may be a little translucenlly brownish towards the base. 

 It is clothed with somewhat long, light brownish to yellowish hairs; 

 also the venter has long hairs. Abdomen is less attenuated than in 

 flavipes, the exterior genitalia are a little larger and show a small 

 hook. The legs are lighter or darker yellowish, the posterior coxæ 

 somewhat darkened; the hind femora and tibiæ dark brown in about 

 the apical half; all tarsi dark except at the base; the anterior femora 

 and the front tibiæ may be a little darkened in the middle. Hind fe- 

 mora a httle thickened, and hind tibiæ distinctly thickened towards 

 the apex. Anterior femora with short hairs above and below; hind 

 femora with long hairs above and below, and on the latter side also 

 with a row of strong, somewhat spine-like bristles; anterior tibiæ 

 short-haired ; hind tibiæ densely ciliated below and with longish hairs 

 above; the last joint on all tarsi with long, bristly hairs above, The 

 hairs are yellowish to brownish. Wings a little dark fumigated. Veins 

 brown or blackish. Stigma brown, quite fiUing the apex of the sub- 

 costal cell. Halteres blackish brown. 



Female. Similar to the male, but the eyes very narrow! y sepa- 

 rated, the facets (so far as I could see) all small; frons black, Thorax 

 black, not æneous; the bristles at the sides of the disc, the hindmost 

 dorsocentral bristle and the scutellar bristles yellow. Abdomen shining. 

 The legs as in the male, but not rarely somewhat lighter, the spine- 

 like bristles below the hind femora absent. Wings hyaline, Halteres 

 yellow. 



Length 2,5 — 3 mm. 



This species is easily distinguished from flavipes by the colour of 

 the legs, the distinctly thickened hind tibiæ, the spine-like bristles be- 

 low the hind femora in the male, the short antennal style and the 

 stigma, which occupies just the apex of the subcostal cell. At first 

 sight it is similar to flavipes, but on closer examination it differs by 

 a multitude of characters. 



T. davipes is not common in Denmark, only eleven specimens 



