The water mites of the genus Atractides Koch, 1837 (Acari, Hydrachnidia: Hygrobatidae) in Corsica and Sardinia

Based on bibliographic data, material from coll. E. Angelier and own field work of the author done in the late 20^th century, a survey is given on the diversity and distribution of spring- and stream-dwelling water mites of the genus Atractides Koch, 1837 on Corsica and Sardinia. Published information on presence of Atractides in the area covered was restricted to Corsica (Angelier 1954a, b; Santucci 1965, 1971, 1977; Giudicelli 1970; Gerecke & Di Sabatino 2013). Redescriptions are given of the incompletely documented species Atractides gracilipes (E. Angelier, 1951) (no more documented by type material) and A. corsicus E. Angelier, 1954 (of which six syntypes could be detected in NHMB). Published records (in brackets) are referred to the species A. robustus (Sokolow, 1940) and A. acutirostris Motaş & Angelier, 1928. In total, 24 Atractides species are now known from the two islands, 50 % of them recorded here for the first time: Atractides allgaier Gerecke, 2003, A. clavipes Lundblad, 1954, A. fonticolus (K. Viets, 1950), A. graecus K. Viets, 1950, A. inflatus (Walter, 1925), A. loricatus Piersing, 1898, A. macrolaminatus Láska, 1956, A. orghidani Motaş & Tanasachi, 1960, A. polyporus (K. Viets, 1922), A. protendens K.O.Viets, 1955, A. spinipes Koch, 1837, A. valencianus K. Viets, 1930. Of the 20 species known from Corsica, nine are first records – from Sardinia all 19 Atractides species are recorded for the first time. Concerning the national faunas, six species are new for Italy (A. allgaier, A. corsicus, A. giustinii Gerecke & Di Sabatino, 2013, A. gracilipes, A. orghidani, A. valencianus), three for France (A. graecus, A. macrolaminatus, A. protendens).