Morphometric and genetic population analysis, overlapping areas and distribution of freshwater silversides from Argentina (Atheriniformes, Atherinopsidae)

MARIELA V. CUELLO; MIRTA L. GARCÍA; GUILLERMO ORTÍ

Mesa redonda; Meeting of School of Biological Sciences, University of Nebraska-Lincoln; 2008

University of Nebraska-Lincoln

Odontesthes Evermann & Kendall 1906 (Dyer, 1993) 20 species (Malabarba y Dyer, 2002) from northen Perú-south Brasil to Tierra del Fuego (Argentina). Freshwater species ranged from northen Chile and Río Grande do Sul, Brasil, to Patagonia (Dyer, 1998). Freshwater species from Argentina include, O. bonariensis O. hatcheri O. humensis O. perugiae O. retropinnis O. argentinensis (typical marine species) are included in this project because they inhabit estuarine and mixohaline environments and overlapping distribution with some others species. Problems Systematic determination is complicated because there are specimens with intermediate morphology among species with overlapping distributions. In addition, there are conections between populations (e.g. Rio de la Plata and Bahia de Samborombon. On other hand, natural distribution of some species like O. bonariensis and O. hatcheri, is growing More overlapping areas the distribution of O. retropinnis, O. humensis and O. perugiae is not precise