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 Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Clade: Paenungulata
Clade: Tethytheria
McKenna 1975
Subclades and orders

Tethytheria is a clade of mammals that includes the sirenians and proboscideans, as well as the extinct order Embrithopoda. [1]

Contents

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. Desmostylians, traditionally considered tethytheres, have been tentatively assigned to Perissodactyla, along with the Early Eocene family Anthracobunidae, which was considered a sister group to Tethytheria. [2] [3]

Systematics

Cladogram modified from Rose 2006 and Cooper et al. 2014. [4]

Afrotheria

Afroinsectiphilia

Paenungulata

Hyracoidea

Tethytheria

Embrithopoda

Proboscidea

Sirenia

Classification

Classification modified from Rose 2006. [2]

Notes

  1. Tethytheria in the Paleobiology Database. Retrieved April 2013.
  2. 1 2 Rose 2006 , pp. 242–3
  3. 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. Bibcode:2014PLoSO...9j9232C. doi: 10.1371/journal.pone.0109232 . PMC   4189980 . PMID   25295875.
  4. Rose 2006 , p. 213

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References