Helicometra fasciata (Rudolphi, 1819) complex from new fish host in the Black sea, the broadnosed pipefish Syngnathus typhle Linnaeus, 1758, with notes on biology of this trematode species

This paper reports on the first record of Helicometra fasciata (Rudolphi, 1819) complex (Opecoelidae) maritae from black-striped pipefish, Syngnathus typhle Linnaeus, 1758, in the Black Sea. Ten fish specimens caught near the Kerch Strait (north-eastern part of the Black Sea) in July 2007 were examined and one of them was found to be parasitized by a single H. fasciata complex ovigerous marita. Description and drawing of the trematode found are given. S. typhle and fish of the Syngnathidae family as a whole are believed to be accidental definitive hosts of H. fasciata complex. Cases of Helicometra spp. ovigerous maritae records in fresh waters are discussed. The expansion of H. fasciata complex definitive host range in the Black Sea ( S. typhle is its 33d known fish host from here) reflects a complexity of food webs in the shelf zone of this sea.