A revision of the West Palaearctic species of Colobostema Enderlein, 1926 (Diptera, Scatopsidae). Part I . European subregion

<p>In this first contribution to the study of the genus Colobostema the European taxa are revised (except those restricted to the Mediterranean subregion), mainly based upon the study of the genitalia and pregenital segment. The occurence of 11 species is reported, all of which are described and figured in the male sex (some also in the female). <strong>Four of these species are described as new</strong>: C. auberti sp.n. (Switzerland, Andorra, Austria, France, Germany, Slovakia, Spain), C. geigeri sp.n. (Switzerland, Germany), C. lastovkai sp.n. (Switzerland, Austria) and C. schertenleibi sp.n. (Switzerland, France, Andorra, Croatia). The quotations of these four species in two faunistic catalogues in the late 1990&rsquo;s must thus be considered as nomina nuda. They are published here again in a way that they meet the criteria of availability, including a formal description. The four following names are formally resurrected from the synonymy: C. flavimanum (Strobl, 1898) comb. n. (Bosnia-Hercegovina, France, Turkey), C. griseinerve (Duda, 1928) comb. n. (Austria, France, Italy, Montenegro, Switzerland), C. infumatum (Haliday, 1833) comb. n. (Ireland, Czech Republic, Great Britain, Norway, Russia, Switzerland) and C. obscuritarse (Strobl, 1898) comb. n. (Austria, Switzerland). New synonymies are established for C. stackelbergi Krivosheina, 2000, junior synonym of C. nigripenne (Meigen, 1830), and for Scatopse sziladyi Zilahi-Sebess, 1956, junior synonym of C. triste (Zetterstedt, 1850). Distributional data are summarized for each species. A key for the identification of males of the European species of Colobostema is provided.</p>