Tethytheria

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Tethytheria
Temporal range: Paleocene-Holocene
Tethytheria 2.jpg
Top: African elephant, Caribbean manatee; middle: Moeritherium, woolly mammoth; bottom: Paleoparadoxia, Arsinoitherium
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Clade: Paenungulata
Clade: Tethytheria
McKenna 1975
Orders

Tethytheria is a clade of mammals that includes the sirenians and proboscideans, as well as the extinct orders Desmostylia and Embrithopoda (desmostylians, however, have been placed in Perissodactyla by a 2014 cladistic analysis[1]).[2]

Though there is strong anatomical and molecular support for the monophyly of Tethytheria, the interrelationships between the included taxa remain disputed. The tethytheres are united by several characters, including anteriorly facing orbits and more or less bilophodont cheek teeth (double transverse ridges on the crowns of the teeth). Proboscidea and Sirenia are linked together based on auditory characters in their petrosal bones, but this link may be a homoplasy. (The Early Eocene family Anthracobunidae has been considered to be a sister group of Tethytheria,[3] but has more recently been assigned to Perissodactyla.[1])

Tethytheria is thought to have evolved from primitive hoofed mammals ("condylarths") along the shores of the ancient Tethys Ocean.

Systematics[edit]

Cladogram after Rose 2006.[4]

Altungulata

Perissodactyla



Paenungulata

Hyracoidea


Tethytheria

Embrithopoda



Desmostylia (?)



Proboscidea



Sirenia







Classification[edit]

Classification after Rose 2006.[3]

Notes[edit]

  1. ^ a b Cooper, L. N.; Seiffert, E. R.; Clementz, M.; Madar, S. I.; Bajpai, S.; Hussain, S. T.; Thewissen, J. G. M. (2014-10-08). "Anthracobunids from the Middle Eocene of India and Pakistan Are Stem Perissodactyls". PLoS ONE. 9 (10): e109232. doi:10.1371/journal.pone.0109232. PMC 4189980Freely accessible. PMID 25295875. 
  2. ^ Tethytheria in the Paleobiology Database. Retrieved April 2013.
  3. ^ a b Rose 2006, pp. 242–3
  4. ^ Rose 2006, p. 213

References[edit]