EN
Thirty-nine species of the shore-fly family Ephydridae that occur on islands of the Republic of Seychelles are reviewed. Included are keys to the appropriate suprageneric categories, genera, and species. Distributional data for all included species are presented, and new taxa are described and illustrated. Six new species are described (type locality in parenthesis): Psilopa victoria (Seychelles. Mahé: Roche Caiman Bird Sanctuary; 4°38.3'S, 55°28.1'E); Cerobothrium insulatum (Seychelles. Mahé: Port Launay; 4°39.2'S, 55°24.2'E); Schema aldabricum (Aldabra. South Island, Flamingo Pool); Orasiopa apiculata (Seychelles. La Digue: La Passe; 4°20.8'S, 55°49.8'E); Polytrichophora specula (Seychelles. Mahé: Anse Boileau (4°42.5'S, 55°28.7'E)); Hyadina munarii (Seychelles. Mahé: Airport). Psilopa giordanii Canzoneri is made a junior subjective synonym of Clasiopella uncinata Hendel, Enchastes scotti Lamb is made a junior subjective synonym of Placopsidella cynocephala Kertész, Hecamedoides pusillus Canzoneri is made junior subjective synonym of Discocerina hepatica de Meijere, Allotrichoma outambense Canzoneri is made a junior subjective synonym of A. argentipraetextum Lamb, and Discocerina (Ditrichophora) rattii Canzoneri is made a junior subjective synonym of Hostis guamensis (Cresson). Asmeringa ligabuei Canzoneri is transferred to the genus Cerobothrium as a new combination. Lectotypes are designated for the following nine species: Discomyza similis Lamb, Ceropsilopa longicornis (Lamb), Psilopa nitidissima Lamb, Allotrichoma argentipraetextum Lamb, Hyadina fenestrata Becker, Zeros fractivirgatus (Lamb), Zeros invenatus (Lamb), Parydra tuberculifera Lamb, Scatella septemfenestrata Lamb. The shore-fly fauna of the Seychelles is diverse, comprising at least 39 species (Table 3), and the populations of these species are generally stable and intact. Most species are adventive to the islands, many apparently being introduced during the last century. Most species have biogeographic connections with the Afrotropical mainland (22 species) and to a lesser extent with the Oriental and Australasian Regions (12 species). The few apparent endemics we identified (7 species or 18%) constitute far less than half the level of endemism that was reported for insect species generally (51%). The freshwater fauna of shore flies on the Seychelles is essentially undeveloped and is comparatively depauperate.