Taxonomy
The species was described by Henri Marie Ducrotay de Blainville in 1817. Rice's 1998 classification lists a single species, Inia geoffrensis in the genus Inia, with three recognized subspecies. Some older classifications, as well as some recent publications, listed the boliviensis population as a separate species. In 2012 the Society for Marine Mammalogy began considering the Bolivian (Inia geoffrensis boliviensis) and Amazonian (Inia geoffrensis geoffrensis) subspecies as full species Inia boliviensis and Inia geoffrensis, respectively; however, much of the scientific community, including the IUCN, consider the boliviensis population to be a subspecies of Inia geoffrensis. The genus Inia separated from its sister taxon during the Miocene epoch.
The two currently recognized species are:
- I. g. geoffrensis — distributed in the Amazon and Araguaia/Tocantins basins (excluding the Madeira River drainage, upstream of the Teotonio Rapids in Rondônia)
- I. g. humboldtiana — distributed in the Orinoco basin
- I. boliviensis — distributed in the Bolivian subbasin of the Amazon basin upstream of the Teotonio Rapids in Rondônia
Read more about this topic: Amazon River Dolphin