Eutherapsida

Reconstruction of Ulemosaurus svijagensis, copyright Dmitry Bogdanov.

Belongs within: Therapsida.
Contains: Dicynodontia, Theriodontia.

The Eutherapsida are the clade of synapsids uniting modern mammals with the Permian Dinocephalia. Members of the clade are characterised by a bowing of the zygomatic arch and increase in size of the temporal fenestra, together with loss of the olecranon ulnae and reduction of the fifth pedal digit to three phalanges.

<==Eutherapsida [Anomodontia, Cryptodontia, Gorgonopsia]S03
    |--+--DicynodontiaS03
    |  `--TheriodontiaS03
    `--DinocephaliaS03
         |  i. s.: RhopalodonTT05
         |         Sinophoneus Cheng & Ji 1996CL97
         |         Microsyodon orloviCL97
         |         EstemmenosuchidaeB93
         |           |--Anoplosuchus tenuirostris Tchudinov 1968B93
         |           |--Zopherosuchus luceus Tchudinov 1983B93
         |           |--Molybdopygus arcanus Tchudinov 1964B93
         |           `--Estemmenosuchus Tchudinov 1960D07
         |                |--E. mirabilis Tchudinov 1968B93
         |                `--E. uralensis Tchudinov 1960B93
         |         TitanosuchidaeB93
         |           |--Titanosuchus Owen 1879D07
         |           |    |--T. cloetiD07
         |           |    `--T. ferox Owen 1879B93
         |           `--Jonkeria Van Hoepen 1916B93, D07
         |                |--J. boonstraiD07
         |                |--J. haughtoniD07
         |                |--J. ingensD07
         |                |--J. koupensisD07
         |                |--J. parvaD07
         |                |--J. rossowiD07
         |                |--J. truculenta Van Hoepen 1916B93
         |                `--J. vanderbyliD07
         |--Stenocybus Cheng & Li 1997 [Stenocybusidae]CL97
         |    `--*S. acidentatus Cheng & Li 1997CL97
         `--+--Tapinocephalidae [Tapinocephalia, Tretospondylia]CL97
            |    |--TapinocephalusC07
            |    |--Tapinocaninus pamelae Rubidge 1988B93
            |    |--Struthiocephalus whaitsi Haughton 1915B93
            |    `--Ulemosaurus Rjabinin 1938TT05, D07
            |         |--U. gigasTT05
            |         `--U. svigagensis Riabinin 1938B93
            `--Anteosauridae [Anteosauria]CL97
                 |--Syodon biarmicum Kutorga 1838B93
                 |--AustralosyodonCL97
                 |--Eosyodon hudsoni Olson 1962B93
                 |--Notosyodon biarmicum Kutorga 1838B93
                 |--Doliosauriscus yanshinovi (Orlov 1958)B93
                 |--Admetophoneus kargalensis Efremov 1954B93
                 |--Paranteosaurus primus Boonstra 1954B93
                 |--Anteosaurus Watson 1921D07
                 |    `--A. magnificus Watson 1921B93
                 |--TitanophoneusCL97
                 |    |--T. adamanteus (Orlov 1958)TT05
                 |    `--T. potens Efremov 1938B93
                 `--DeuterosaurusB93
                      |--D. biarmicus Eichwald 1860B93
                      `--D. jubilaei (von Nopcsa 1928)TT05
Eutherapsida incertae sedis:
  Theriognathus Broom 1920C07, D07
    `--T. micropsD07
  Endothiodontidae [Endothiodontia]B93
    |--EndothiodonC07
    `--Chelydontops altidentalis Cluver 1975B93
  DromasauriaR61
    |  i. s.: GalechirusR61
    |--Galeops [Galeopidae]R61
    |    `--G. whaitsi Broom 1912B93
    `--DromasauridaeB93
         |--Patronomodon nyaphulii Rubidge & Hopson 1991B93
         `--Galepus jouberti Broom 1910R61, B93
  Watongia [Watongiidae]B93
    `--W. meieri Olson 1974B93
  Eodicynodon [Eodicynodontidae]B93
    `--E. oosthuizeni Barry 1974B93
  CryptodontidaeB93
    |--Tropidostoma microtrema (Seeley 1889)B93
    |--Cteniosaurus platyceps Broom 1935B93
    |--Rhachiocephalus magnus (Owen 1876)B93
    `--Oudenodon baini Owen 1860B93

*Type species of generic name indicated

References

[B93] Benton, M. J. 1993. Reptilia. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 681–715. Chapman & Hall: London.

[C07] Case, E. C. 1907. Revision of the Pelycosauria of North America. Carnegie Institute of Washington Publication 55: 1–176, 35 pls.

[CL97] Cheng Z. & Li J. 1997. A new genus of primitive dinocephalian—the third report on Late Permian Dashankou lower tetrapod fauna. Vertebrata PalAsiatica 35 (1): 35–43.

[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.

[R61] Romer, A. S. 1961. Synapsid evolution and dentition. In: Vandebroek, G. (ed.) International Colloquium on the Evolution of Lower and Non Specialized Mammals. Koninklijke Vlaames Academie voor Wetenschappen, Letteren en Schone Kunsten van Belgie—Klasse der Wetenschapen 1961 (1): 9–56.

[S03] Sidor, C. A. 2003. The naris and palate of Lycaenodon longiceps (Therapsida: Biarmosuchia), with comments on their early evolution in the Therapsida. Journal of Paleontology 77 (5): 977–984.

[TT05] Tverdokhlebov, V. P., G. I. Tverdokhlebova, A. V. Minikh, M. V. Surkov & M. J. Benton. 2005. Upper Permian vertebrates and their sedimentological context in the South Urals, Russia. Earth-Science Reviews 69: 27–77.

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