Filogenia molecular e revisão taxonômica de hemiancistrus bleeker, 1862 (Siluriformes : loricariidae)

Detalhes bibliográficos
Ano de defesa: 2020
Autor(a) principal: Meza-Vargas, Sonia Vanessa lattes
Orientador(a): Reis, Roberto Esser dos lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Tese
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
Programa de Pós-Graduação: Programa de Pós Graduação em Ecologia e Evolução da Biodiversidade
Departamento: Escola de Ciências da Saúde e da Vida
País: Brasil
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/10004
Resumo: Hemiancistrus has a complex history, both taxonomic and phylogenetically. Since the description of Hemiancistrus in the XIX Century, the lack of precision in the diagnostic traits of the genus contributed to the confusion with other genera until today. Currently, Hemiancistrus has 12 valid species widely distributed in South America. Although the last study of the genus represents a considerable advance, there is still difficulties to identify them correctly. Aiming at having a better understanding of Hemiancistrus and related taxa, a molecular-based phylogenetic and a taxonomic revision are presented. The phylogeny is based on seven molecular markers, four mitochondrial (16S, coI, cytb e nd2) and three nuclear (rag1, rag2 e myh6), and the data matrix is composed by 107 terminals. The ingroup contains several genera of Hypostominae, including all species of Hemiancistrus, and the outgroup contains representatives of other subfamilies in Loricariidae. Bayesian Inference and Maximum Likelihood analyses were conducted using a concatenated data matrix of 5,467 characters. Both analyses were highly congruent and recovered Hemiancistrus polyphyletic. The results served as a basis to support propositions of new genera. The Hemiancistrus Clade includes Baryancistrus, `Baryancistrus` demantoides (Orinoco), Hemiancistrus, Panaque, Parancistrus, and Spectracanthicus. In this clade, Hemiancistrus is monotypic, only including the type species, and the `B.` demantoides species group represents a new genus composed of four species. Also, `H.` landoni and `H.` furtivus (Pacific), belonging to the Peckoltia Clade, are described as another new genus. The tribe Hypostomini is composed by `Hemiancistrus` cerrado (Tocantins), the clade `Hemiancistrus` chlorostictus (South), with six nominal species, Hypostomus, `Hypostomus` annectens, and Pterygoplichthys. Both clades H.` chlorostictus (South) and `H.` cerrado (Tocantins) are also described as new genera. Descriptions of all new genera are provided based on external morphological characters, as well as redescriptions and taxonomic comments of all of their species. Geographic distribution maps and identification keys are given for the `B.` demantoides and H.` chlorostictus species groups. Finally, members of the Hypostomini and valid species for Baryancistrus are discussed.