Thalassoleon

Taxobox
name = "Thalassoleon"
fossil_range = Late Miocene

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image_caption = "Thalassoleon mexicanus"
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Carnivora
subordo = Caniformia
superfamilia = Pinnipedia
familia = Otariidae
familia_authority = Gray, 1825
genus = "Thalassoleon"
genus_authority = Repenning and Tedford 1977
subdivision_ranks = Species
subdivision =
* "T. mexicanus"
* "T. inouei"
* "T. macnallyae"

"Thalassoleon" (literally "Ocean Lion") is an extinct genus of large extinct fur seal. "Thalassoleon" inhabited the Northern Pacific ocean in latest Miocene and early Pliocene time. Fossils of "T. mexicanus" are known from Baja California and southern California. "T. macnallyae" is known from central California, and "T. inouei" (which may be a synonym of "T. macnallyae") is known from Japan. "Thalassoleon" could be the ancestor of the modern Northern Fur Seal.