''Cynthiacetus'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of basilosaurid early whale that lived during the

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'', "d ...

(

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 ...

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 (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

and

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

( Otuma Formation).

Description

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

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 s ...

'' '' 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 long.

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