Xenorophus

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Xenorophus
Temporal range: Late Oligocene, 28.4–23.0  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Xenorophidae
Genus: Xenorophus
Kellogg, 1923
Species

X. sloaniiKellogg, 1923
X. simplicidensBoessenecker & Geisler, 2023

Contents

Xenorophus is a genus of primitive odontocete from late Oligocene (Chattian) marine deposits in South Carolina. It belongs to the Xenorophidae.

Classification

Xenorophus was originally described on the basis of a skull from the Chandler Bridge Formation of South Carolina in the collections of the USNM. [1] Later authors, but also Remington Kellogg who described the genus, classified it in the family Agorophiidae, which eventually became a repository for primitive odontocetes. Whitmore and Sanders (1977) and Fordyce (1981), however, preferred to treat Xenorophus as Odontoceti incertae sedis. [2] [3] [4] [5] A cladistic analysis by Mark Uhen published in 2008 recognized Xenorophus as belonging with Archaeodelphis and Albertodelphis in an odontocete clade more primitive than Agorophius or Simocetus , and named it Xenorophidae. [6]

Paleobiology

Xenorophus was capable of echolocation like modern dolphins, judging from the cranial features of two other xenorophids, Echovenator and Cotylocara [7] [8] and from the shape of its own skull. [9] It had an estimated body length of 2.6 to 3 metres (8 ft 6 in to 9 ft 10 in). [9]

Related Research Articles

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<i>Squalodon</i> Extinct genus of mammals

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<i>Aetiocetus</i> Extinct genus of mammals

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<i>Australodelphis</i> Extinct genus of mammals

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<span class="mw-page-title-main">Xenorophidae</span> Extinct family of mammals

Xenorophidae is an extinct family of odontocetes, currently known from the Oligocene of the Southeastern United States. Known genera of xenorophids include Albertocetus, Archaeodelphis, Xenorophus, Cotylocara, Echovenator, and Inermorostrum.

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<i>Agorophius</i> Extinct species of whale

Agorophius is an extinct genus of toothed whale that lived during the Oligocene period, approximately 32 million years ago, in the waters off what is now South Carolina.

<i>Mirocetus</i> Extinct genus of whale-like animals

Mirocetus is a genus of archaic odontocete from the late Oligocene (Chattian) of Azerbaijan. Like many other primitive odontocetes, its classification has been fluid since its description.

<i>Cotylocara</i> Extinct genus of odontocete cetaceans

Cotylocara is a genus of primitive odontocete from late Oligocene (Chattian) marine deposits of the Chandler Bridge Formation of South Carolina. It belongs to the Xenorophidae.

<i>Albertocetus</i> Extinct genus of mammals

Albertocetus is an extinct genus of primitive odontocete cetacean from early Oligocene (Rupelian) marine deposits in North Carolina, and belonging to the family Xenorophidae.

Archaeodelphis is an extinct genus of primitive odontocete cetacean from late Oligocene (Chattian) marine deposits in South Carolina, and belonging to the family Xenorophidae.

References

  1. R. Kellogg. 1923. Description of an apparently new toothed cetacean from South Carolina. Smithsonian Miscellaneous Collections 76(7):1-7
  2. R. Kellogg. 1928. The History of Whales - Their Adaptation to Life in the Water. The Quarterly Review of Biology 3(1):29-76.
  3. F. C. Whitmore and A. E. Sanders. 1977. Review of the Oligocene Cetacea. Systematic Zoology 25:304-320.
  4. R. E. Fordyce. 1981. Systematics of the odontocete whale Agorophius pygmaeus and the Family Agorophiidae (Mammalia: Cetacea). Journal of Paleontology 55(5):1028-1045.
  5. G. G. Simpson. 1945. The principles of classification and a classification of mammals. Bulletin of the American Museum of Natural History 85:1-350.
  6. Uhen, M.D. (2008). "A new Xenorophus-like odontocete cetacean from the Oligocene of North Carolina and a discussion of the basal odontocete radiation". Journal of Systematic Palaeontology. 6 (4): 433–452. doi:10.1017/S1477201908002472. S2CID   86668273.
  7. Geisler, J.H.; Colbert, M.W.; Carew, J.L. (2014). "A new fossil species supports an early origin for toothed whale echolocation". Nature. 508 (7496): 383–386. Bibcode:2014Natur.508..383G. doi:10.1038/nature13086. PMID   24670659. S2CID   4457391.
  8. Churchill, M.; Martinez-Caceres, M.; et al. (2016). "The origin of high-frequency hearing in whales". Current Biology. 26 (16): 2144–2149. doi: 10.1016/j.cub.2016.06.004 . PMID   27498568. S2CID   3944589.
  9. 1 2 Boessenecker, R.W.; Geisler, J.H. (November 2023). "New skeletons of the ancient dolphin Xenorophus sloanii and Xenorophus simplicidens sp. nov. (Mammalia, Cetacea) from the Oligocene of South Carolina and the ontogeny, functional anatomy, asymmetry, pathology, and evolution of the earliest Odontoceti". Diversity. 15 (11): 1154. doi: 10.3390/d15111154 .