The Bunocephalus coracoideus Species Complex (Siluriformes, Aspredinidae). Signs of a Speciation Process through Chromosomal, Genetic and Ecological Diversity.

摘要: Bunocephalus is the most species-rich Aspredinidae genus, corresponding to a monophyletic clade with 13 valid species. However, many species have their classification put in question. Here, we analyzed individuals from four Amazonian populations of coracoideus by cytogenetic and molecular procedures. The geographic distribution, genetic distances karyotype data indicate that each population represents an Evolutionary Significant Unit (ESU). Cytogenetic markers showed distinct 2n formulas, as well different numbers locations rDNA sites among ESUs. One such (ESU-D) highlighted extensive polymorphic condition, several cytotypes probably due chromosomal rearrangements meiotic non-disjunctions. This resulted aneuploid karyotypes, which was also supported mapping telomeric sequences. Phylograms based on Maximum Likelihood (ML) Neighbor Joining (NJ) analyses grouped ESU particular highly clades, estimation evolutionary divergence indicating values being higher than 3.8-12.3% them. Our study reveals huge degree diversity B. points existence ESUs allopatric sympatric speciation processes. In fact, high divergences found allowed us delimitate lineages taxonomic uncertainties this nominal