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Diversity of Creptotrema was investigated using morphological and molecular tools, including data for Creptotrema creptotrema (type-species). Three new species, parasites of Brazilian fishes, are described: Creptotrema conconae n. sp. (type-host, Imparfinis mirini Haseman), Creptotrema schubarti n. sp. (type-host, Characidium schubarti Travassos) and Creptotrema megacetabularis n. sp. (type-host, Auchenipterus osteomystax (Miranda Ribeiro)). The diagnosis of the genus was amended to include new features. The new species differ from each other mainly in terms of body shape, relative sucker size, and testes position. DNA sequences were obtained from Creptotrema spp. from Brazil, including 28S, ITS and COI. Genetic divergences among the new species and C. creptotrema varied from 2.1 to 5.2% (21-49 bp) for 28S, and 6.6 to 16.4% (21-45 bp) for COI. Phylogenetic analysis (28S) placed the newly generated DNA sequences of Creptotrema in a clade (Creptotrema clade sensu stricto) composed of C. creptotrema, the new species described herein, and all species previously described as Auriculostoma, revealing that Auriculostoma is best interpreted as a synonym of Creptotrema based on the principle of priority of zoological nomenclature. Creptotrema funduli, the single sequence of the genus previously available, was not grouped within the Creptotrema clade sensu stricto, suggesting the need for reevaluation of the taxonomic status of this species. Our results showed that Creptotrema represents a monophyletic genus of trematodes widely distributed across the Americas, which currently comprises 19 valid species of parasites of teleosts and anurans.

TITLE: Trois nouvelles espèces de Creptotrema (Trematoda, Allocreadiidae) avec diagnostic modifié du genre et une réattribution d'Auriculostoma (Allocreadiidae) sur la base de preuves morphologiques et moléculaires. ABSTRACT: La diversité de Creptotrema a été étudiée à l'aide d'outils morphologiques et moléculaires, incluant des données pour Creptotrema creptotrema (espèce-type). Trois nouvelles espèces, parasites de poissons brésiliens, sont décrites : Creptotrema conconae n. sp. (hôte-type, Imparfinis mirini Haseman), Creptotrema schubarti n. sp. (hôte-type, Characidium schubarti Travassos) et Creptotrema megacetabularis n. sp. (hôte-type, Auchenipterus osteomystax (Miranda Ribeiro)). Le diagnostic du genre a été modifié pour inclure de nouvelles caractéristiques. Les nouvelles espèces diffèrent les unes des autres principalement en termes de forme du corps, de taille relative des ventouses et de position des testicules. Des séquences d'ADN ont été obtenues de Creptotrema spp. du Brésil, y compris 28S, ITS et COI. Les divergences génétiques entre les nouvelles espèces et C. creptotrema variaient de 2,1 à 5,2 % (21 à 49 pb) pour les séquences 28S, et de 6,6 à 16,4 % (21 à 45 pb) pour le COI. L'analyse phylogénétique (28S) a placé les séquences d'ADN nouvellement générées de Creptotrema dans un clade (Creptotrema clade sensu stricto) composé de C. creptotrema, les nouvelles espèces décrites ici et toutes les espèces précédemment décrites comme Auriculostoma, révélant qu'Auriculostoma est mieux interprété comme un synonyme de Creptotrema sur la base du principe de priorité de la nomenclature zoologique. Creptotrema funduli, la seule séquence du genre précédemment disponible, n'a pas été regroupée au sein du clade Creptotrema sensu stricto, ce qui suggère la nécessité d'une réévaluation du statut taxonomique de cette espèce. Nos résultats montrent que Creptotrema est un genre monophylétique de trématodes largement distribué à travers les Amériques, qui comprend actuellement 19 espèces valides, parasites de téléostéens et d'anoures.

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PURPOSE: To describe three new species of Cosmetocleithrum in the gills of Trachelyopterus galeatus (Siluriformes, Auchenipteridae) from Aguapeí River, Upper Paraná River basin, São Paulo State, Brazil. METHODS: Fifty-three specimens of T. galeatus were captured in the mouth of the Aguapeí River from August 2013 to June 2014. Monogeneans were mounted unstained in Hoyer's and Gray and Wess's medium. RESULTS: Cosmetocleithrum spathulatum sp. n., Cosmetocleithrum baculum sp. n., and Cosmetocleithrum galeatum sp. n. differ from all known congeneric species mainly in the morphology of the accessory piece (i.e. spatulate-shaped, claviform, and a straight rod with hook-shaped distal portion, respectively). Also, the three new species share hooks with different sizes with hooks pairs 5 and 7 bigger than others and with an erect delicate point, inconspicuous thumb, longer shaft, and slender shank. CONCLUSIONS: To date, 18 species of Cosmetocleithrum were recognised parasitizing siluriforms in the Neotropical region. The present study expands the number to 21 species, however, despite this increase, the number of known taxa of monogeneans in neotropics is far from representing the ideal situation.

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Seven new species of Urocleidoides from the gills and skin of nine Neotropical fish hosts (Anostomidae, Parodontidae, and Gymnotidae) are described: Urocleidoides digitabulum n. sp. on Leporinus friderici, Leporinus octofasciatus, and Megaleporinus elongatus (Anostomidae); Urocleidoides solarivaginatus n. sp. on L. friderici, L. octofasciatus, and Leporinus striatus (Anostomidae); Urocleidoides falxus n. sp. and Urocleidoides sapucaiensis n. sp. on M. elongatus; Urocleidoides tenuis n. sp. on Apareiodon piracicabae and Apareiodon affinis (Parodontidae); Urocleidoides sinus n. sp. on L. striatus, Schizodon nasutus, and Schizodon intermedius (Anostomidae); and Urocleidoides uncinus n. sp. on Gymnotus sylvius (Gymnotidae). Urocleidoides paradoxus was also found in this study on L. friderici and included in the phylogenetic analysis. Molecular data (partial 28S rDNA and mitochondrial cytochrome oxidase subunit I) were obtained for U. digitabulum n. sp., U. tenuis n. sp., U. sinus n. sp., and U. uncinus n. sp. The identification of Urocleidoides is amended herein to include all taxonomic modifications observed in this genus over time and add new characteristics observed in the species in the present study. Phylogenetic analysis revealed Urocleidoides digitabulum n. sp. and Urocleidoides sinus n. sp. (parasites of anostomids) closely related in the tree topologies. Furthermore, the new species described herein parasitized phylogenetically distant host species (Characiformes and Gymnotiformes), suggesting the effect of the dynamic process of ecological fitting.

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