LIFE-CYCLE, DELIMITATION AND REDESCRIPTION OF CATATROPIS-VERRUCOSA (FROLICH, 1789) ODHNER, 1905 (TREMATODA, NOTOCOTYLIDAE)

The life-cycle of Catatropis verrucosa (Frolich, 1789) Odhner, 1905 ha s been completed experimentally starting from infected snails collecte d along the River Danube in Europe. Each stage of the life-cycle is re described. Taxonomic problems are discussed and the main features of t he species are listed. Synonyms for C. verrucosa are Fasciola verrucos a Frolich, 1789, F. anseris Gmelin, 1790, Monostoma verrucosa (Frolich , 1789) Zeder, 1800, and Catatropis charadrii Skrjabin, 1915. Other na mes, such as Notocotylus triserialis Diesing, 1839, Notocotyle triseri ale (Diesing, 1839) Diesing, 1850, Monostoma verrugueux: Dujardin, 184 5, ''Monostoma sp. du canard'' of Blanchard (1847), Notocotyle verruco sum (Frolich, 1789) Monticelli, 1892, N. verruqueux Railliet, 1895, an d Distoma verrucosum (Frolich, 1789) Wolffhugel, 1900, were found to r epresent adults and/or larvae of C. verrucosa. Conversely, but less of ten, adults and larvae of other species were found described and illus trated as C. verrucosa. One of these, C. verrucosa of Joyeux (1922), w as renamed Pseudocatatropis joyeuxi Kanev & Vassilev, 1986. Occasional ly, authors actually working with C. verrucosa ascribed their results to different species. Based on experimental lifecycle studies, the fol lowing facts were demonstrated. (1) The first intermediate hosts are t he prosobranch freshwater snails Bithynia tentaculata (Linnaeus, 1758) and B. leachi (Leach, 1818). (2) The same snails are also first inter mediate hosts for Notocotylus imbricatus (Looss, 1893) Szidat, 1935, N . parviovatus Yamaguti, 1934, and N. ponticus Tschiaberaschvili, 1966. In all these species, the species characteristics are expressed by th e adult morphology only, and the larvae cannot be identified by morpho logical criteria. It is proposed that tri-oculate monostome cercariae found in naturally infected B. tentaculata and B. lenchi be referred t o as ''Cercaria imbricata group''. These cercariae include Cercaria im bricata Looss, 1893, C. helvetica I Dubois, 1928, C. triophthalmia Fau st, 1930, C. fennica I Wikgren, 1956; C. ephemera of Lutta (1934); C. monostomi of Mathias (1925), Lutta (1934) and Zdun (1961), Cercaria No tocotylus attenuatus of Francalanci & Manfredini (1969), and Monostome cercaria I Emmel, 1943. (3) There is no second intermediate snail hos t in the life-cycle of C. verrucosa. (4) The final hosts are birds. (5 ) The adult worms possess, on the ventral body surface, a median ridge and two lateral rows of 12 (range 11-14) papillae per row.