''Chrysocetus'' (from Greek ''chrysous'', "golden", and ''ketos'', "whale", in reference to the gold-colored bones of the type specimen) is a genus of extinct early whale known from Late Eocene-aged fossils of the eastern United States and western Africa.

Taxonomy

The type species, ''Chrysocetus healyorum'', is based on a single subadult specimen from the late middle or early late

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

Orangeburg County Orangeburg County is a county located in the U.S. state of South Carolina. As of the 2020 census, the population was 92,501. Its county seat is Orangeburg. The county was created in 1769. Orangeburg County comprises the Orangeburg, SC Mi ...

, South Carolina (, paleocoordinates ). The holotype, SCSM 87.195, consists of a partial skull with lower jaws, ten teeth, and the

hyoid The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. ...

apparatus; 21 vertebrae, some ribs and a sternum; a partial left forelimb; and partial innominates. A second species, ''Chrysocetus fouadassii'', is known from

Bartonian The Bartonian is, in the ICS's geologic time scale, a stage or age in the middle Eocene Epoch or Series. The Bartonian Age spans the time between . It is preceded by the Lutetian and is followed by the Priabonian Age. Stratigraphic defin ...

-age deposits in the

Western Sahara Western Sahara ( '; ; ) is a disputed territory on the northwest coast and in the Maghreb region of North and West Africa. About 20% of the territory is controlled by the self-proclaimed Sahrawi Arab Democratic Republic (SADR), while ...

.Philip D. Gingerich and Samir Zouhri (2015). "New fauna of archaeocete whales (Mammalia, Cetacea) from the Bartonian middle Eocene of southern Morocco". Journal of African Earth Sciences 111: 273–286. doi:10.1016/j.jafrearsci.2015.08.006.

Description

''Chrysocetus'' is similar to ''

Zygorhiza ''Zygorhiza'' ("Yoke-Root") is an extinct genus of basilosaurid early whale known from the Late Eocene (Priabonian, 38–34 Ma) of Louisiana, Alabama, and Mississippi, United States, and the Bartonian (43–37 Ma on the New Zealand geologic tim ...

'' except that it lacks the denticles on the cingula of the upper premolars characteristic of ''Zygorhiza''. The premolars of ''Chrysocetus'' have smoother enamel than other dorudontines and are more gracile than those of ''

Dorudon ''Dorudon'' ("spear-tooth") is a genus of extinct basilosaurid ancient whales that lived alongside '' Basilosaurus'' 40.4 to 33.9 million years ago in the Eocene. It was a small whale, with ''D. atrox'' measuring long and weighing . ''Dorudon' ...

''.

Notes

References

* Basilosauridae Prehistoric cetacean genera Eocene mammals of Africa Eocene mammals of North America Eocene United States Fossil taxa described in 2001 {{paleo-whale-stub