Article · Wikipedia archive · Last revised Jun 9, 2026

Cornwallius

Cornwallius is an extinct herbivorous marine mammal of the family Desmostylidae. Cornwallius lived along the North American Pacific Coast from the Early Oligocene (Chattian) into the Early Miocene and existing for approximately 7.8 million years.

Last revised
Jun 9, 2026
Read time
≈ 1 min
Length
255 w
Citations
5
Source
Cornwallius
Temporal range:
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Placentalia
Order: Desmostylia
Family: Desmostylidae
Genus: Cornwallius
Hay 1923
Species:
C. sookensis
Binomial name
Cornwallius sookensis

Cornwallius is an extinct herbivorous marine mammal of the family Desmostylidae. Cornwallius lived along the North American Pacific Coast from the Early Oligocene (Chattian) into the Early Miocene (28.4 mya—20.6 Mya) and existing for approximately 7.8 million years.12

The type locality is the Chattian Sooke Formation, Vancouver Island, British Columbia, Canada (48°24′N 123°54′W / 48.4°N 123.9°W / 48.4; -123.9, paleocoordinates 48°00′N 115°00′W / 48.0°N 115.0°W / 48.0; -115.0).2

Cornwallius was named by Hay 1923. Its type is Desmostylus sookensis, named by Cornwall 1922 and recombined to Cornwallius sookensis by Hay 1923.3

Fossils have been discovered from Baja California Peninsula, Oregon and Washington coasts, and Unalaska Island.4

Notes

Notes

  1. Cornwallius in the Paleobiology Database. Retrieved 16 June 2013.
  2. Muir Creek (Oligocene of Canada) in the Paleobiology Database. Retrieved 16 June 2013.
  3. Cornwallius sookensis in the Paleobiology Database. Retrieved 16 June 2013.
  4. Beatty 2006b
References

References