title: Promiscuous speciation with gene flow in silverside fish genus Odontesthes (Atheriniformes, Atherinopsidae) from south western Atlantic Ocean basins.
abstract: The present paper integrates phylogenetic and population genetics analyses based on mitochondrial and nuclear molecular markers in silversides, genus Odontesthes, from a non-sampled area in the SW Atlantic Ocean to address species discrimination and to define Managements Units for sustainable conservation. All phylogenetic analyses based on the COI mitochondrial gene were consistent to support the monophyly of the genus Odontesthes and to include O. argentinensis, O. perugiae-humensis and some O. bonariensis haplotypes in a basal polytomy conforming a major derivative clade. Microsatellites data revealed somewhat higher genetic variability values in the O. argentinensis-perugia populations than in O. bonariensis and O. perugia-humensis taxa. Contrasting population genetics structuring emerged from mitochondrial and microsatellites analyses in these taxa. Whereas mitochondrial data supported two major groups (O. argentinensis-perugia-humensis vs. O. bonariensis-perugiae-humensis populations), microsatellite data detected three major genetic entities represented by O. bonariensis, O. perugiae-humensis and an admixture of populations belonging to O. argentinensis-perugiae respectively. Therefore, the star COI polytomy in the tree topology involving these taxa could be interpreted by several hypothetic scenarios such as the existence of shared ancestral polymorphisms, incomplete lineage sorting in a radiating speciation process and/or reticulation events. Present findings support that promiscuous and recent contact between incipient species sharing asymmetric gene flow exchanges, blurs taxa boundaries yielding complicated taxonomy and Management Units delimitation in silverside genus Odontesthes from SW Atlantic Ocean basins.
authors.affiliation: Sección Genética Evolutiva, Facultad de Ciencias, UdelaR, Montevideo, Uruguay.
authors.forename: Graciela
authors.initials: G
authors.lastname: García
authors.affiliation: Sección Genética Evolutiva, Facultad de Ciencias, UdelaR, Montevideo, Uruguay.
authors.forename: Néstor
authors.initials: N
authors.lastname: Ríos
authors.affiliation: Sección Genética Evolutiva, Facultad de Ciencias, UdelaR, Montevideo, Uruguay.
authors.forename: Verónica
authors.initials: V
authors.lastname: Gutiérrez
authors.affiliation: Departamento de Genética, Facultad de Veterinaria, Campus de Lugo, Universidad de Santiago de Compostela, Lugo, Spain.
authors.forename: Jorge Guerra
authors.initials: JG
authors.lastname: Varela
authors.affiliation: Departamento de Genética, Facultad de Veterinaria, Campus de Lugo, Universidad de Santiago de Compostela, Lugo, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Bouza Fernández
authors.affiliation: Departamento de Genética, Facultad de Veterinaria, Campus de Lugo, Universidad de Santiago de Compostela, Lugo, Spain.
authors.forename: Belén Gómez
authors.initials: BG
authors.lastname: Pardo
authors.affiliation: Departamento de Genética, Facultad de Veterinaria, Campus de Lugo, Universidad de Santiago de Compostela, Lugo, Spain.
authors.forename: Paulino Martínez
authors.initials: PM
authors.lastname: Portela
mesh_terms: D000818:Animals; D001267:Atlantic Ocean; D001483:Base Sequence; D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D005399:Fishes / Q000145:classification* / Q000235:genetics; D051456:Gene Flow / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics*; D008928:Mitochondria / Q000235:genetics*; D010802:Phylogeny; D058974:Phylogeography; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial