''Mixocetus'' is a genus of extinct baleen whale belonging to the family Tranatocetidae. It is known only from the late

Miocene The Miocene ( ) is the first 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 means "less recen ...

(

Tortonian The Tortonian is in the geologic time scale an age or stage of the late Miocene that spans the time between 11.608 ± 0.005 Ma and 7.246 ± 0.005 Ma (million years ago). It follows the Serravallian and is followed by the Messinian. The Torton ...

) of

Los Angeles County Los Angeles County, officially the County of Los Angeles, and sometimes abbreviated as L.A. County, is the most populous county in the United States and in the U.S. state of California, with 9,861,224 residents estimated as of 2022. It is the ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

Description

''Mixocetus'' is a large-size mysticete with a long, narrow rostrum, a robust braincase, a nostril opening extending posteriorly just a few inches behind the antorbital processes, the posterior ends of the premaxillae, maxillae, and nasals tapering and extending posteriorly to a point between superior parts of supraorbital processes of the frontals, and a temporal fossa opening dorsally. Unlike ''Cetotherium'', the antorbital process is larger, the lateral margins of the supraoccipital processes of the frontals are parallel to each other, there is a protruding lateral wall of the braincase, and the rear portion of the cranium has a very thick and posteriorly protruding exoccipital.M. D. Uhen, R. E. Fordyce, and L. G. Barnes. 2008. Odontoceti. In C. M. Janis, K. M. Scott, and L. L. Jacobs (eds.), Evolution of Tertiary Mammals of North America II:566-606

Taxonomy

The holotype of this species is LACM 882. It was collected from the Modelo Formation (early Tortonian, 10-11.6 Ma) of Lincoln Heights in Los Angeles County, California. It now resides as a permanent exhibit at the

Natural History Museum of Los Angeles County The Natural History Museum of Los Angeles County is the largest natural and historical museum in the western United States. Its collections include nearly 35 million specimens and artifacts and cover 4.5 billion years of history. This large coll ...

in Exposition Park,

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

References

{{Taxonbar, from=Q18346143 Baleen whales Miocene cetaceans Miocene mammals of North America Prehistoric cetacean genera Fossil taxa described in 1934 Taxa named by Remington Kellogg