Notocetus

Notocetus is an extinct genus of river dolphin belonging to Squalodelphinidae. Known specimens have been found in Early Miocene marine deposits from Argentina, Italy and Peru.
Taxonomy.
"Notocetus" was unnecessarily given the replacement name "Diochoticus" by Ameghino (1894) on the false assumption that "Notocetus" was preoccupied by "Notiocetus". Lydekker (1894), meanwhile erected "Argyrodelphis" for the same specimen. The type species of "Otekaikea" was once considered a species of "Notocetus" before being recognized as belonging to Waipatiidae.
Distribution.
Fossils of "Notocetus" have been found in: