Reappraisal of Goezeella Fuhrmann, 1916 (Cestoda: Proteocephalidae), parasites of Neotropical catfishes (Siluriformes), with description of a new species from Pimelodella cristata (Heptapteridae)

Abstract

The cestode genus GoezeellaFuhrmann, 1916 is reviewed on the basis of taxonomic evaluation of type and newly collected material from pimelodid and heptapterid catfishes (Siluriformes) in the Amazon River basin, South America, and its generic diagnosis is amended. The genus is typified by the exclusively ventral position of the cortical vitelline follicles, the inner longitudinal musculature formed by dense individual muscle fibres, rather than forming bundles as in other proteocephalids, a well-developed metascolex and biloculate suckers. The type species, G. siluriFuhrmann, 1916, is redescribed based on its syntype from Cetopsis coecutiens (type-host) (Cetopsidae) and specimens from Pinirampus pirinampu (Pimelodidae). The validity of G. danbrooksi de Chambrier, Rego & Mariaux, 2004 from Ageneiosus pardalis (Auchenipteridae) is confirmed and some erroneous morphological traits are corrected based on examination of its holotype. A new species, Goezeella mariae sp. nov., is described from the heptapterid catfish Pimelodella cristata (Heptapteridae). The new species differs from congeners by its overall size (much smaller compared to G. siluri), morphology of the scolex (strongly wrinkled metascolex and weakly developed interlocular septum of suckers) and number of the testes. This is the third proteocephalid cestode described from a heptapterid catfish in South America and the first helminth parasite reported from P. cristata. Goezeella is unusual among other Neotropical proteocephalids by its occurrence in catfishes of as many as four families; all species of the genus are known only from the Amazon and Orinoco River basins. Molecular data on two of the three valid species and a key to their identification are provided.