PARARETINOMETRA LATERALACANTHA STOCK AND HOLMES, 1981 (CESTODA, HYMENOLEPIDIDAE) - THE FIRST RECORD IN THE PALEARCTIC REGION AND COMMENTS ON ITS MORPHOLOGY AND TAXONOMY

Pararetinometra lateralacantha Stock and Holmes, 1981, known until now only from Alberta, Canada, as a parasite of three species of grebes ( Aves: Podicipediformes: Podicipedidae), was found in a wintering Podic eps nigricollis (Brehm) on the Bulgarian coast of the Black Sea. The s pecies is redescribed and illustrated on the basis of both the Bulgari an specimens and specimens from Canada (paratypes). Some corrections o r additions to the original description in relation to the characteris tics of the rostellum, rostellar sheath, vitellarium, ovary, testes, c irrus sac, cirrus, and vagina are presented. In contrast to a recent o pinion, Pararetinometra Stock and Holmes, 1981 is regarded as a valid genus and not as a synonym of Cladogynia Baer, 1937. The geographical distribution of P. lateralacantha is supposed to be circumboreal.