Anatomia e relações filogenéticas da família Loricariidae (Ostariophysi: Siluriformes) com ênfase na subfamília Hypoptopomatinae

• Ano de defesa: 2006
• Autor(a) principal: Albornoz, Pablo Cesar Lehmann
• Orientador(a): Reis, Roberto Esser dos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
• Palavras-chave em Português: BIOLOGIA; ZOOLOGIA; ICTIOLOGIA; PEIXES
• Link de acesso: http://hdl.handle.net/10923/5444

The anatomy and osteology of Parotocinclus maculicauda (Steindachner, 1877) is described and compared with other loricariids and astroblepids examined. The skeleton of Parotocinclus maculicauda exhibits fusions, reductions of size and number of bones, among others. New structures of bony elements not previously described in traditional literature are described. In addition, this hypoptopomine was used as a descriptive model in the search for informative characters for the phylogenetic study of the subfamily Hypoptopomatinae. Based on 169 characters of osteology and external morphology, a phylogenetic analysis of 114 terminal loricariid taxa, especially of the subfamilies Hypoptopomatinae and Neoplecostominae was performed. The results allow to rediagnose the subfamily Hypoptopomatinae, recognizing 24 genera. Five monophyletic assemblages are recognized as new genera and 30 new species are identified. We found no support for a monophyletic Otothyrini and hence tribes previously recognized within Hypoptopomatinae are not maintained in this study. The inclusion of representatives of other loricariid subfamilies in the analyses provided a better understanding of loricariid phylogenetic relationships and biodiversity. Complementarily, a new species of the hypoptopomatine catfish genus Otocinclus is described from two localities in the upper Río Amazonas basin. The new taxon can be easily distinguished from all congeners but Otocinclus cocama by the heavily pigmented single bat-shaped spot on the posterior portion of caudal fin. From O. cocama it is distinguished by color pattern, consisting of a wide dark lateral stripe. The new species is possibly more closely related to a clade formed by O. huaorani, O. mariae, O. bororo, O. mura, and O. cocama. Finally, Otocinclus arnoldi from the La Plata basin is resurrected from the synonymy of O. flexilis, described from rio Jacuí basin.Also, Otocinclus mimulus from a tributary of the Río Paraná drainage is considered as a junior synonym of Otocinclus arnoldi.