Potamotrygon motoro, Potamotrygon scobina, and Potamotrygon orbignyi
We found that three of the four species with broadest distribution in the Amazon basin (the fourth species Paratrygon aiereba was not included in this study), species which also are highly polymorphic, were not reciprocally monophyletic, and extensively shared haplotypes among species. Haplotype sharing may indicate that i) taxonomic validity of these species should be reassessed; ii) lineages did not have enough time to reach reciprocally monophyly; iii) hybridization; or iv) combination of these factors (Moritz and Cicero, 2004).