Rhagionidae Latreille, 1802

Rhagionidae are small to large, slender flies, with a body length from 2.0 to 20.0 mm. Body colour yellowish to dark, often with a yellow pattern. Males usually holoptic and females dichoptic, antennal flagellum compact, with a subapical style or arista, rounded, onion-shaped or reniform. Wing venation indicating a relationship to other Tabanomorpha; infumations or dark markings on wings not rare. Legs slender, with spurs on mid and hind tibiae. Larval head capsule slender, mostly retracted within thorax; creeping welts distinct on abdominal segments; respiratory system amphipneustic, with posterior spiracles surrounded by four lobes of anal segment. The larvae live in damp soil rich in decaying organic matter, but some species prefer rotten wood, mosses and mud at the edge of running water. The larvae are mostly predaceous, but some are also saprophagous whilst those of Spania are leaf-miners in liverworts. The adults are predaceous; species of Rhagio are often found sitting on the trunks of solitary trees with the head directed downwards.

92 species in seven genera are known in Europe (Majer 2007). 27 species are included in this checklist, with 24 in the Czech Republic (24 in Bohemia and 23 in Moravia) and 26 in Slovakia. No additional species have been recorded since the PCV2 (Rozkošný & Spitzer 1997) but one omitted species is added here.

The characteristics of the family have been given by Majer (1997). The Central European species may be identified using the key by Rozkošný and Spitzer (1965), whilst faunistic data from the Czech Republic were summarised by Spitzer and Barták (2000). Nomenclature follows the the Fauna Europaea (Majer 2007).

For financial support, the Ministry of Education of the Czech Republic and the Masaryk University (grant No. MSM 0021622416)are acknowledged.