Kentriodontidae is an extinct family of

odontocete The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of t ...

whales related to modern

dolphins A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (t ...

. The Kentriodontidae lived from the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

to the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

Taxonomy

Kentriodontids have been variously divided into three or four subfamilies: Kampholophinae, Kentriodontinae, Lophocetinae, and Pithanodelphinae. However, recent cladistic studies have recovered Kentriodontidae as paraphyletic. Pyenson ND Vélez-Juarbe J Gutstein CS Little H Vigil D O’Dea A . 2015. Isthminia panamensis, a new fossil inioid (Mammalia, Cetacea) from the Chagres Formation of Panama and the evolution of ‘river dolphins’ in the Americas. PeerJ 3: e1227.O. Lambert, G. Bianucci, M. Urbina and J. H. Geisler. 2017. A new inioid (Cetacea, Odontoceti, Delphinida) from the Miocene of Peru and the origin of modern dolphin and porpoise families. Zoological Journal of the Linnean Society 179:919-946. For instance, ''"Lophocetus" pappus'' may be a close relative of

Lipotidae Lipotidae is a family of river dolphins containing the possibly extinct baiji of China and the fossil genus ''Parapontoporia'' from the Late Miocene and Pliocene of the Pacific coast of North America. The genus '' Prolipotes'', which is based on ...

, '' "Delphinodon" dividum'' is basal to other delphinidans, '' Incacetus'' is probably a member of

Inioidea River dolphins are a polyphyletic group of fully aquatic mammals that reside exclusively in freshwater or brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea. Extant riv ...

, and ''Atocetus'' and ''Lophocetus'' have been recovered as a pontoporiid and ziphiid sister taxon respectively, while ''

Hadrodelphis ''Hadrodelphis'' is an extinct genus of dolphin once assigned to the paraphyletic/polyphyletic family Kentriodontidae. Remains have been found in the middle Miocene (Langhian) Calvert Formation of United States. Taxonomy ''Harodelphis'' is simil ...

'', ''Kampholophos'', ''

Macrokentriodon ''Macrokentriodon'' is an extinct genus of giant dolphin once assigned to the paraphyletic/polyphyletic family Kentriodontidae. Remains have been found in the late Miocene (Serravallian) Choptank Formation of United States. ''Macrokentriodon'' ...

'', and ''"Lophocetus" pappus'' are recovered in a clade phylogenetically intermediate between ''Kentriodon'' and derived delphinidans ((Inioidea+Lipotidae)+Delphinoidea). Peredo et al. (2018) restrict Kentriodon to ''Kampholophos'', ''Kentriodon'', ''Rudicetus'', and ''Wimahl'', and remove Pithanodelphininae and its putative constituent genera ('' Leptodelphis'', '' Pithanodelphis'', '' Sarmatodelphis'', '' Sophianacetus'', and '' Tagicetus'') as well as '' Microphocaena'' from Kentriodontidae.Carlos Mauricio Peredo, Mark D. Uhen & Margot D. Nelson (2018): A new kentriodontid (Cetacea: Odontoceti) from the early Miocene Astoria Formation and a revision of the stem delphinidan family Kentriodontidae, Journal of Vertebrate Paleontology, DOI: 10.1080/02724634.2017.1411357

Genera

* '' Kampholophos'' * ''

Kentriodon ''Kentriodon'' is an extinct genus of Odontoceti, toothed whale related to modern-day dolphins. Fossils have been found in North America, Europe and Japan. Several species have been described. Description ''Kentriodon'' was the most diverse ...

'' * '' Rudicetus'' * '' Sophianaecetus'' * '' Wimahl'' * '' Belonodelphis''? * '' Liolithax''?

Notes

References

* Ichishima, H., Barnes, L. G., Fordyce, R. E., Kimura, M. and Bohaska, D. J. (1994), A review of kentriodontine dolphins (Cetacea; Deiphinoidea; Kentriodontidae): Systematics and biogeography. ''Island Arc'', 3: 486–492. doi
10.1111/j.1440-1738.1994.tb00127.x
* 2005: A new kentriodontid (Cetacea: Delphinoidea) from the Middle Miocene of Hungary. ''Mitteilungen aus dem Museum fuer Naturkunde in Berlin Geowissenschaftliche Reihe'', 8: 53–73. * 2006: ''Sophianaecetus'', a replacement name for ''Mediocris'' (Cetacea: Delphinoidea: Kentriodontidae). ''Fossil record'', 9: 260. * 2006: The generic name ''Mediocris'' (Cetacea: Delphinoidea: Kentriodontidae), belongs to a foraminiferan. ''Fossil record'', 9: 259. Prehistoric toothed whales Oligocene cetaceans Miocene cetaceans Pliocene cetaceans Oligocene first appearances Pliocene extinctions Prehistoric mammal families {{paleo-whale-stub