''Macrodelphinus'' is an extinct genus of primitive

odontocete The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales with teeth, such as beaked whales and the sperm whales. 73 species of toothed whales are ...

known from Early

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

marine deposits in California.

Biology

''Macrodelphinus'' was an

orca The orca (''Orcinus orca''), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. The only extant species in the genus '' Orcinus'', it is recognizable by its black-and-white-patterned body. A cosmopol ...

-sized odontocete similar to members of Eurhinodelphinidae in having a swordfish-like rostrum and upper jaw. Because of its size, and inch-long teeth, it is believed to have been an

apex predator An apex predator, also known as a top predator or superpredator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the hig ...

Classification

''Macrodelphinus'' is known from a fragmentary skull from the Early Miocene Jewett Sand Formation of

Kern County Kern County is a county (United States), county located in the U.S. state of California. As of the 2020 United States census, 2020 census, the population was 909,235. Its county seat is Bakersfield, California, Bakersfield. Kern County compris ...

, southern California. Although often classified as a member of Eurhinodelphinidae, the cladistic analysis of '' Chilcacetus'' recovers it outside Eurhinodelphinidae, less advanced than '' Eoplatanista''. The Miocene species ''"Champsodelphis" valenciennesii'' Brandt, 1873, based on a rostrum fragment from marine sediments in Landes, France, was assigned to ''Macrodelphinus'' by Kellogg (1944).R. Kellogg. 1944. Fossil Cetaceans from the Florida Tertiary. Bulletin of the Museum of Comparative Zoology at Harvard College XCIV(9):433-471.

References

* Miocene mammals of North America Prehistoric toothed whales Miocene cetaceans Prehistoric cetacean genera Fossil taxa described in 1935 {{paleo-whale-stub