Freshwater stingray diversity (Chondrichthyes Potamotrygonidae) in the Amazon estuary

Abstract

A survey of the occurrence reports on the freshwater stingrays (Potamotrygonidae) in the Amazon estuary  was carried out as from the literature, on-line scientific collection databanks and field sampling. The results indicated  the presence of eight nominal species:  Plesiotrygon iwamae ,  Paratrygon aiereba ,  Potamotrygon humerosa,  Potamotrygon motoro, Potamotrygon cf.  ocellata ,  Potamotrygon orbignyi, Potamotrygon scobina and  Potamotrygon aff.  hystrix . Only five of these are presently considered scientifically valid. Additionally, at least two  other species and a genus are currently being described. The total number of species in the Amazon estuary is uncertain  and may vary between five and ten depending on the systematic advances and revisions that will take place in this  elasmobranch group.