Periscelis Loew, 1858

Mathis, Wayne N. & Freidberg, Amnon, 2012, Periscelis stuckenbergi sp. n., the first record of the genus from the Afrotropical Region (Diptera: Periscelididae: Periscelidinae), African Invertebrates 53 (1), pp. 231-231 : 234

Genus Periscelis Loew, 1858

Periscelis: Loew 1858: 113 (Type species: Periscelis annulipes Loew, 1858 , by subsequent designation ( Sturtevant 1923: 1)); Schiner 1863: 271 [revision European species]; Becker 1905: 217 [Palaearctic catalogue]; Duda 1934: 5 [revision Palaearctic species]; Papp 1984: 233–234 [Palaearctic catalogue]; 1988: 273–284 [discussion, figures]; Mathis & Rung 2011: 353–358 [world catalogue].

Diagnosis: Head: Face distinctly angulate or with a protruding, transverse carina (best seen in lateral view); dorsal half of face narrow, not distinctly and broadly flattened or shield­like, ventral half of face lacking transverse furrows. Eyes normal, not borne on conspicuous stalks. Thorax: Scutellum broadly rounded apically, lacking patch of long setae apically. Chaetotaxy as follows: 2 posterior dorsocentral setae; presutural seta lacking; prescutellar acrostichal setae variable, depending on species­group. Wing mostly hyaline; apical section of vein M straight or very shallowly arched; vein R 1 bare dorsally; vein R 2+3 more­or­less evenly arched throughout, except for a small section just before apex. Abdomen: Male terminalia (based only on P. wheeleri ( Sturtevant, 1923) and P. occidentalis Sturtevant, 1954 ): epandrium and surstyli connected with internal structures of terminalia; cercus moderately well sclerotised, longer than wide, porrect posteriorly, not narrowed apically, bearing several moderately long setae, but lacking stout, tooth­like setae at apex; surstyli fused with ventral margin of epandrium, asymmetrical or symmetrical, narrow and rounded apically, bearing sparse, short setulae on apical half; a well­sclerotised process joining base of surstylus; gonite distinct and comparatively long, tapered ventrally, shorter than surstylus.