''Castor californicus'' is an extinct species of
beaver
Beavers (genus ''Castor'') are large, semiaquatic rodents of the Northern Hemisphere. There are two existing species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers are the second-large ...
that lived in western
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
from the end of the
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 ...
to the early
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
.
''Castor californicus'' was first discovered in the
Kettleman Hills of
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
, United States. The species was similar to but larger than the extant North American beaver, ''
C. canadensis''.
Unlike other members of the ''Castor'' genus, ''Castor californicus'' possessed a total of three enamel folds, the folds of the internal enamel epithelium.
Phylogenetic characteristics
''Castor californicus'' has been determined to be the earliest type of its genus to appear in North America.
''Castor californicus'' is characterized by having short nasal passages. The backs of their skulls were quite wide in comparison to other members of the ''Castor'' genus. The coronoid process is more spread out. Their pterygoid muscles were on the larger side, and their neck muscles were broad. Due to these distinctions, ''Castor californicus'' had a slight physical advantage compared to ''
Castor fiber
The Eurasian beaver (''Castor fiber'') or European beaver is a species of beaver widespread across Eurasia, with a rapidly increasing population of at least 1.5 million in 2020. The Eurasian beaver was hunted to near-extinction for both its fur ...
'', the extant European beaver. Each ''Castor californicus'' speciemn examined was slightly unique in its postcranial morphology. They had short femurs and elongated hind feet, which assisted them in moving with ease through water.
Compared to other species of beavers, ''Castor californicus'' had considerably wide metatarsals, which aided them in the swimming and digging process.
''Castor californicus'' has three folds of the internal enamel epithelium, unlike other members of the ''Castor'' genus.
References
Further reading
*
*
External links
{{Taxonbar, from=Q3495788
Prehistoric beavers
Prehistoric mammals of North America
Miocene rodents
Pleistocene rodents
†
Taxa named by Vernon Lyman Kellogg
Fossil taxa described in 1911