Full text
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| Author(s): |
Cláudia Tangerino Olivares
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) |
| Defense date: | 2014-08-14 |
| Examining board members: |
Fernando Portella de Luna Marques;
Walter Antonio Pereira Boeger;
Florian Reyda
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| Advisor: | Fernando Portella de Luna Marques |
| Abstract | |
Stingrays of the Potamotrygonidae family (Chondrichthyes: Myliobatoidei) are endemic elasmobranchs of river systems in the Neotropics. In these hosts a reside diverse fauna of parasite which includes many genera of tapeworms (Cestoda). Both stingrays and their cestodes are derived from marine ancestors. However, the taxonomy and systematics of this host/parasite system is poorly known. This study documents, for the first time, the molecular diversity of Potamotrygonocestus lineages by employing the direct optimization of 28S rDNA, ITS1 rDNA, Calmodulin and Cytochrome Oxidase I genes. The goal of this study is to understand the phylogenetic position of its members within a cladistic analysis. The results support the monophyly of the genus Potamotrygonocestus and recovered two main clades morphologically diagnosed based on hook morphology hook. The phylogenetic hypothesis presented supports the contention that P. chaoi and P. marajoara are junior synonyms of P. travassosi, and P. orinoconoensis should be considered a valid specie. Additionally, the results suggest that there are 14 new lineages that can be raised to the level of species. Members of Potamotrygonocestus proved to be more host specific than previously thought and, in relation to its biogeography, the phylogenetic hypothesis presented mirrors similar patterns of area association reported for many members of the Neotropical ichthyofauna. The expansion of biogeographical representativeness and inclusion of the molecular data in systematics of the genus allowed the recognition of distribution and infestation patterns that were previously unknown. This refinement could be interesting for other potamotrigonids genus parasites (AU) | |
| FAPESP's process: | 11/15946-1 - Molecular systematics of Potamotrygonocestus Brooks & Thorson, 1976 (Eucestoda: Tetraphyllidea: Onchobothriidae) |
| Grantee: | Cláudia Tangerino Olivares |
| Support Opportunities: | Scholarships in Brazil - Master |