J. Helminthol. Soc. Wash. 64(2), 1997 pp. 208-218 Neotropical Monogenoidea. 30. Ancyrocephalinae (Dactylogyridae) of Piranha and Their Relatives (Teleostei, Serrasalmidae) from Brazil: Species of Calpidothecium gen. n., Calpidothecioides gen. n., Odothecium gen. n., and Notothecioides gen. n. DELANE C. KRiTSKY,1-4 WALTER A. BoEGER,2 AND MICHEL JEGU3 1 College of Health Professions, Idaho State University, Pocatello, Idaho 83209 (e-mail:
[email protected]), 2 Departamento de Zoologia, Universidade Federal do Parana, Caixa Postal 19020, Curitiba, Parana 81530, Brazil, and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) (e-mail:
[email protected]), and 3 Antenne ORSTOM, Laboratoire d'Ichtyologie, MNHN, 43 rue Cuvier 75231 Paris Cedex, France (e-mail:jegu@ mnhn.fr) ABSTRACT: Two species of Calpidothecium, 2 species (1 new) of Calpidothecioides, 1 new species of Odo- thecium, and 1 new species of Notothecioides (Dactylogyridae, Ancyrocephalinae) are described and/or reported from the gills of 4 species of Serrasalmidae from the Brazilian Amazon: Calpidothecium crescentis (Mizelle and Price, 1965) comb. n. (syn. Urocleidus crescentis Mizelle and Price, 1965), C. serrasalmus (Mizelle and Price, 1965) comb. n. (syn. Cleidodiscus serrasalmus Mizelle and Price, 1965), and Calpidothecioides pygopristi sp. n. from Pygopristis denticulata; Odothecium raphidiophallum sp. n. from Catoprion mento; and Notothe- cioides llewellyni sp. n. from Myleus torquatus and M. rubripinnis. Four new genera are proposed: Calpido- thecium is characterized