Proteocefal?deos (Eucestoda: Onchoproteocephalidea) parasitos de peixes na Am?rica do Sul: uma abordagem taxon?mica integrativa

• Ano de defesa: 2018
• Autor(a) principal: Alves, Philippe Vieira
• Orientador(a): Alejos, Jos? Luis Fernando Luque
• Banca de defesa: Arredondo, Nathalia Jaquelina , Silva, Claudia Portes Santos , Lima, Sueli de Souza , Muniz-Pereira, Lu?s Cl?udio
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Biologia Animal
• Departamento: Instituto de Ci?ncias Biol?gicas e da Sa?de
• País: Brasil
• Palavras-chave em Português: Morfologia; Filogenia molecular; Proteocephalidae; Peixes dulc?colas
• Palavras-chave em Inglês: Morfologia; Molecular phylogeny; Proteocephalidae; Freshwater fishes
• Área do conhecimento CNPq: Zoologia
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/5001

South America has the highest diversity of freshwater fishes (teleosts) in the world, which in turn, may serve as definitive host for an also diverse fauna of proteocephalidean tapeworms (Eucestoda: Onchoproteocephalidea), even though robust and unequivocal studies on this group are scarce in this continent. In the present study, an integrated taxonomic approach of morphological and molecular data was used to better understand the diversity of proteocephalids in South American fishes. Between May 2013 and October 2015, a total of 330 specimens of fish were necropsied from Brazilian river systems as well as 7 specimens of Odonthestes bonariensis from an Argentinian lake. These hosts were collected by artisanal fishermen and immediately (in situ) scrutinized for parasites. The proteocephalids found were evaluated using light and scanning electron microscopy, some of them were further processed for sequencing of the large subunit nuclear ribosomal RNA gene (28S rDNA, D1?D3 domains). Neotropical proteocephalids deposited in helminthological collections (type material or not yet described specimens) were also evaluated. In thechapter I, the genus Frezella was proposed to accommodate Frezella vaucheri exTocantinsia piresi from Xing? River, State of Par?. Phylogenetic analyses confirmed the validity of F. vaucheri. In the chapter II, the genus Chambriella is revised based on specimens from the Amazon and Parana river basins; as a result, Lenhataenia became a junior synonym of Chambriella and its type species, C. agostinhoi ex Zungaro jahu (type host) e Z. zungaro, a junior synonym of C. megacephala. The second species of Chambriella, C. paranaensis ex Hemisorubim platyrhynchos, was transferred to a new genus, Riggenbachiella, as R. paranaense. Riggenbachiella amazonense ex Sorubimichthys planiceps (type host), Phractocephalus hemioliopterus and Z. zungaro was described and designated as the type-species of the new genus. All taxonomic actions were supported by molecular analyses. In the chapter III, the genus Goezeella was revised based on the redescription of its type species, G. siluri ex Cetopsis coecutiens (type host) and Pinirampus pirinampu, confirmation of the validity of G. danbrooksi ex Ageneiosus pardalis, and the description of G. mariae ex Pimelodella cristata from the lower Amazon River, State of Amap?. Molecular data on two of the three valid species and a key to their identification were provided. In the chapter IV, the diagnoses of two monotypic genera, Ephedrocephalus and Zygobothrium, were amended and their species, E. microcephalus and Z. megacephalum ex P. hemioliopterus (host for both taxa), were redescribed. Furthermore, a key for the identification of proteocephalid species that parasitize P. hemioliopterus was also provided. This work reinforces the idea that the knowledge on the fauna of proteocephalid cestodes in South America is incipient and fragmentary, and the use of the 28S rDNA gene may be important for discriminating individual taxa, but does not help,significantly, in the reconstruction of the evolutionary history of the Neotropical clades.