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.^[1][2]

Notocetus Temporal range: Early Miocene ~20.43–16 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Infraorder:	Cetacea
Family:	†Squalodelphinidae
Genus:	†Notocetus Moreno, 1892
Species:	†N. vanbenedeni
Binomial name
†Notocetus vanbenedeni Moreno, 1892
Synonyms
Argyrodelphis Lydekker, 1894 Diochotichus Ameghino, 1894 Diochoticus Ameghino, 1894

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.^[3][4] The type species of Otekaikea was once considered a species of Notocetus before being recognized as belonging to Waipatiidae.^[5][6]

Distribution

Fossils of Notocetus have been found in:^[7]

• Monte León Formation, Argentina
• Pietra Leccese Formation, Italy
• Chilcatay Formation, Peru

Palaeobiology

Palaeoecology

Paired analysis of the ultrastructure of its enamel, which was thin in the anterior teeth and thick in the posterior teeth, and its skull morphology suggests that N. vanbenedeni was a suction feeder.^[8]