Bibionidae Fleming, 1821

Small to large (3.0-15.0 mm) nematocerous flies with a strong sexual dimorphism that is evident in both the morphology (eyes holoptic in males, broadly separated in females) and the colour. Bibionids are robust flies with a setose body, swollen fore femur, and fore tibia armed with series of spines (Dilophus) or strong apical spurs (Bibio). Antenna short with transverse antennomeres. Palpi four-segmented, longer than antenna. Wing with anterior veins darkened and posterior ones usually depigmented, basal radial and basal medials cells long, and R5 unforked in Bibionidae (s. s.) sensu e.g Krivosheina (1986). The phytosaprophagous larvae develop in decaying vegetable matter or leaf litter, and some species may become pests of crops while feeding on the roots of grasses and subterranean parts of plants.

The Bibionidae is a small family comprising about 700 world species (Skartveit 1997), of which about 40 species occur in Europe. Altogether 19 species are known from the Czech Republic (Bosák & Haenni 2006, Haenni & Barták 2000, Haenni et al. 2005) and 18 from Slovakia (Bosák & Haenni 2006, Pecina 1984, Roháček et al. 1995). One species, Dilophus antipedalis Wiedemann in Meigen, 1818, which was erroneously mentioned in previous versions of the checklist (Pecina 1987, 1997), is deleted following Bosák and Haenni (2006) while another species has been added very recently (Haenni et al. 2005). On the other hand, some older records were overlooked in the preceding checklists. The species richness of the bibionid fauna is well known in the Czech Republic and Slovakia. The nomenclature and classification of the present list follow the Fauna Europaea (Skartveit 2007), with some changes including treating the Pleciinae as a separate family.