Molecular systematics of Potamotrygonocestus Brooks & Thorson, 1976 (Eucestoda: Tetraphyllidea: Onchobothriidae)

• Grant number: 11/18947-9
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2012
• End date: June 30, 2014
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: Fernando Portella de Luna Marques
• Grantee: Fernando Portella de Luna Marques
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Molecular techniques have been useful throughout Biology and have been incorporated within many its disciplines due to their ability to compile data very fast and efficiently to be used to address relevant scientific questions. An example could be how molecular systematics have used nucleotide sequence data under the expectation that they could help to solve questions regarding species boundaries that were not able to be resolved using morphological data alone. An important model which require unambiguous species identification are host/parasite systems. Neotropical freshwater stingrays of the family Potamotrygonids (Chondrichthyes: Myliobatoidei) are an interesting group of elasmobranchs restricted to river systems of South America in which you find a diverse fauna of helminths. Within this fauna resides members of Potamotrygonocestus (Cestoda: Tetraphyllidea), a group of tapeworms for which we recognize 11 valid species. The phylogenetic relationships within Potamotrygonocestus have been addressed in the past based on morphological data, but none of the two existing hypotheses contemplate the present diversity of the group. Here, I intent to revisit the phylogeny of Potamotrygononestus and refine its taxonomy by incorporating molecular data to the present dataset under the expectation that it will provide a better understand of the evolution of this group. In summary, it is expected that the addition of molecular data will allow us to test the present concept of the nominal species within the genus and provide a phylogenetic hypothesis that would allow the identification of biogeographical and co-evolutionary events responsible for the diversification of this group of parasites. (AU)