''Cynthiacetus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of basilosaurid early whale that lived during the

Late Eocene The Priabonian is, in the International Commission on Stratigraphy, ICS's geologic timescale, the latest age (geology), age or the upper stage (stratigraphy), stage of the Eocene epoch (geology), Epoch or series (stratigraphy), Series. It spans ...

(

Bartonian The Bartonian is, in the International Commission on Stratigraphy's (ICS) geologic time scale, a stage or age in the middle of the Eocene Epoch or Series. The Bartonian Age spans the time between . It is preceded by the Lutetian and is follow ...

Priabonian The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between . The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage ...

, .) Specimens have been found in the southeastern

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

( Otuma Formation).

Discovery and naming

''Cynthiacetus'' was named after the town of Cynthia, Mississippi, close to where the type specimen for the species ''C. maxwelli'' was discovered.

Description

The skull of ''C. maxwelli'' was similar in size and morphology to that of ''

Basilosaurus ''Basilosaurus'' (meaning "king lizard") is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago (mya). First described in 1834, it was the first archaeocete and prehisto ...

cetoides'', but ''Cynthiacetus'' lacked the elongated vertebrae of ''Basilosaurus''. erected the genus to avoid the ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

'' '' Pontogeneus'' (which was based on poorly described and now vanished specimens). ''Cynthiacetus'' was smaller than '' Masracetus''. The South American species ''C. peruvianus'', the first archaeocete to be described on that continent, mainly differs from ''C. maxwelli'' in the number of cuspids in the lower premolars, but it also has the greatest numbers of thoracic vertebrae (20). The type specimen of ''C. peruvianus'' belonged to an adult individual measuring around long and weighing up to .

References

Bibliography

* * * * Basilosauridae Prehistoric cetacean genera Eocene mammals of North America Paleogene United States Fossils of Georgia (U.S. state) Paleontology in Mississippi Fossils of North Carolina Eocene mammals of South America Tinguirirican Paleogene Peru Fossils of Peru Fossil taxa described in 2005 {{paleo-whale-stub