Rugilus Leach, 1819

Rugilus includes more than 200 species and is almost cosmopolitan in distribution. Various subgeneric divisions are proposed but these are incomplete and in this sense the genus needs to be revised, similarly modern research has produced many new species, especially from the Eastern Palaearctic and Oriental regions, and so any subgeneric groupings are likely to be changed. The Palaearctic and Oriental regions include about 95 species, 76 of which are included in the predominantly western nominate subgenus, 16 eastern species are included in the predominantly eastern subgenus Eurystilicus Fagel, 1953 and 2 are of uncertain placement. The European fauna includes 16 species of Rugilus s.str. as well as R. nematideus Gistel, 1857 and R. salicetorum Gistel, 1857, both endemic to Germany and of uncertain subgeneric placement. Further afield 13 species are known from North America, of which 4 are adventive, and 39 species are known from South and Central America. The Afrotropical region, including Madagascar, is very diverse with about 117 species, but only 2 non-native species are known from Australia although Papua New Guinea. Of the European species only 7 (R. angustatus (Geoffroy, 1785), R. rufipes Germar, 1836, R. subtilis (Erichson, 1840), R. orbiculatus (Paykull, 1789), R. erichsoni (Fauvel, 1867), R. similis (Erichson, 1839) and R. geniculatus (Erichson, 1839)) are widespread and extend north to the UK although of these R. similis is absent from much of Western Europe. The only other widespread species is R. mixtus (Lohse, 1956) which occurs throughout Central Europe but is not known from the UK. Of the rest; R. rossi (Zanetti, 1977) is known from Italy and the Near East, and R. festivus (Mulsant & Rey, 1853) occurs in south west Europe and North Africa, the others are endemic to certain areas: R. sardous (Lohse, 1956) to Sardinia, R. dilutipes (Reitter, 1884) to Greece, R. graditanus (Peyerimhoff, 1937) and R. ibiricus (Fagel, 1959) to Spain, R. pecticensis (Coiffait, 1939) to France and R. maltzevi Gusarov, 1991 to Ukraine. Most species occur in organic detritus, moss and decaying wood etc. in a wide variety of permanently damp or wet habitats. Adults of most species are present year-round and many species are capable of flight. A few species e.g. R. orbiculatus and R. rufipes have become widely dispersed across the world with trade in horticultural and agricultural products etc.