Morfometria de Rhizoprionodon porosus e R. terraenovae (Chondrichthyes, Charcharhinidae) utilizando técnicas de análise multivariada para determinação do status específico

Abstract

The status of the two distinct the species Rhizoprionodon porosus and Rhizoprionodon terraenovae is not yet ascertained. The identification at the species level of fishery resources is imperative not only for their own ecologic value, but also under the point of view of their management. Multivariate analyses of a set of phenotypic characters can be considered as an appropriate method to elucidate morphologic relations between different species or populations. The morphologic discrimination standards between Rhizoprionodon porosus and Rhizoprionodon terraenovae has been studied through techniques of multivariate analysis with the aim to evaluate the status of the species and to determine which morphometric characters can be used in the discrimination. On basis of 79 individuals collected in 3 localities (Pernamuco e Rio Grande do Norte, Brasil e Flórida, EUA) and 67 paratyps of both species deposited in the Museums MN/UFRJ, MZUSP, MOVI, MNHN and FMNH, Multivariate analyses have been carried out on the basis of 64 morphometric measurements. The results indicate differences between Rhizoprionodon porosus and Rhizoprionodon terraenovae. Distinct groups of both species formed clusters and were analyzed by discriminant analyzes. Units with divergent classification correspond to the region of Central America. Overall, differences suggested that they are two distinct simpatricas species highly miscegenated in the area of Central America.