Reptiliomorpha

Mounted skeleton of Diadectes sideropelicus, from here.

Belongs within: Neostegalia.
Contains: Synapsida, Reptilia, Lepospondyli.

The Reptiliomorpha are the group of animals more closely related to modern amniotes (reptiles and mammals) than to modern batrachians (frogs and salamanders). As well as the amniotes themselves, reptiliomorphs include the Carboniferous and Permian 'anthracosaurs' and lepospondyls, two groups traditionally classed as amphibians. Commonly regarded as the sister group of amniotes are the Diadectomorpha of the Late Carboniferous to Early Permian, some members of which reached large sizes such as the herbivorous Diadectidae. The Seymouriamorpha are a primarily Permian group that have been described as reptile-like but which retained some plesiomorphic features such as external gills.

Reptiliomorpha [Anthracosauria, Anthracosauroideae]
    |  i. s.: Eldeceeon rolfei Smithson 1994 RCQ03
    |         Neopteroplax conemaughensis S85
    |--Silvanerpeton miripedes Clack 1994 AC08, RCQ03
    `--+--Gephyrostegidae [Gephyrostegoidea] RCQ03
       |    |--Bruktererpeton fiebigi Boy & Bandel 1973 RCQ03
       |    `--Gephyrostegus bohemicus Jaekel 1902 RCQ03
       `--Batrachosauria [Diadecta, Gymnodermia] LR95
            |--Solenodonsaurus Broili 1924 RCQ03, D07
            |    `--S. janenschi Broili 1924 RCQ03
            `--+--Seymouriamorpha RCQ03
               |    |  i. s.: Enosuchus [Enosuchidae] TT05
               |    |           `--E. breviceps (Konzhukova 1955) TT05
               |    |         Karpinskiosauridae TT05
               |    |           |--Buzulukia butsuri V’yushkov 1957 TT05
               |    |           `--Karpinskiosaurus TT05
               |    |                |--K. secundus Ivakhnenko 1987 TT05
               |    |                `--K. ultimus (Chudinov & V’yushkov 1956) TT05
               |    |         Chroniosuchidae TT05
               |    |           |--Chroniosaurus dongusensis (Tverdokhlebova 1972) TT05
               |    |           |--Chroniosuchus paradoxus V’yushkov 1957 TT05
               |    |           `--Jarilinus mirabilis (V’yushkov 1957) TT05
               |    |--Kotlassiidae RCQ03
               |    |    |--Kotlassia prima Amalitsky 1921 RCQ03
               |    |    `--Microphon exiguus Ivakhnenko 1983 TT05
               |    `--+--Ariekanerpeton RCQ03
               |       |--Discosauriscus [Discosauriscidae] RCQ03
               |       |    `--D. austriacus (Makowsky 1876) RCQ03
               |       `--Seymouria White 1939 RCQ03, D07 [Seymouriidae M06]
               |            |--S. baylorensis Broili 1904 RCQ03
               |            |--S. graandis D07
               |            `--S. sanjuanensis Vaughn 1966 RCQ03
               `--Cotylosauria LR95
                    |--Amniota [Euamniota, Haemothermia, Mononaralia] RCQ03
                    |    |  i. s.: Casineria Smithson & Clack 1999 RCQ03, D07
                    |    |           `--C. kiddi RCQ03
                    |    |         Apsisaurus witteri D-SMS06
                    |    |         Cynodraco major C07
                    |    |         Cynosuchus C07
                    |    |         Nythosaurus C07
                    |    |         Scalaposaurus C07
                    |    |         Otocoelidae [Chelydosauridae] C07
                    |    |           |--Otocoelus C07
                    |    |           `--Conodectes C07
                    |    |--Synapsida M06
                    |    `--+--Reptilia M06
                    |       `--+--Lepospondyli PS17
                    |          |--Westlothiana Smithson 1989 RCQ03, D07
                    |          |    `--W. lizziae Smithson & Rolfe 1990 RCQ03
                    |          `--Opisthodontosaurus carrolli PS17
                    `--Diadectomorpha RCQ03
                         |--Tseajaia RCQ03 [Tseajaiidae LR95]
                         |    `--T. campi Vaughn 1964 RCQ03
                         |--Limnoscelis [Limnoscelidae, Limnosceloidea] M06
                         |    |--L. dynatis M06
                         |    `--L. paludis Williston 1911 RCQ03
                         `--Diadectidae M06
                              |--Helodectes C07
                              |    |--H. isacii C07
                              |    `--H. paridens C07
                              |--Diadectes Watson 1917 D07
                              |    |--D. absitus Berman, Sumida & Martens 1998 RCQ03
                              |    |--D. phaseolinus C07
                              |    `--D. sideropelicus C07
                              `--Empedocles C07
                                   |--E. alatus C07
                                   |--E. latibuccatus C07
                                   `--E. molaris C07

*Type species of generic name indicated

REFERENCES

[AC08] Ahlberg, P. E., J. A. Clack, E. Lukševičs, H. Blom & I. Zupiņš. 2008. Ventastega curonica and the origin of tetrapod morphology. Nature 453: 1199–1204.

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

[D-SMS06] Dias-da-Silva, S., S. P. Modesto & C. L. Schultz. 2006. New material of Procolophon (Parareptilia: Procolophonoidea) from the Lower Triassic of Brazil, with remarks on the ages of the Sanga do Cabral and Buena Vista formations of South America. Canadian Journal of Earth Sciences 43: 1685–1693.

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

[LR95] Laurin, M., & R. R. Reisz. 1995. A reevaluation of early amniote phylogeny. Zoological Journal of the Linnean Society 113: 165–223.

[M06] Modesto, S. P. 2006. The cranial skeleton of the Early Permian aquatic reptile Mesosaurus tenuidens: implications for relationships and palaeobiology. Zoological Journal of the Linnean Society 146: 345–368.

[PS17] Pardo, J. D., M. Szostakiwskyj, P. E. Ahlberg & J. S. Anderson. 2017. Hidden morphological diversity among early tetrapods. Nature 546: 642–645.

[RCQ03] Ruta, M., M. I. Coates & D. L. J. Quicke. 2003. Early tetrapod relationships revisited. Biological Reviews 78: 251–345.

[S85] Smithson, T. R. 1985. The morphology and relationships of the Carboniferous amphibian Eoherpeton watsoni Panchen. Zoological Journal of the Linnean Society 85: 317–410.

[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.

Last updated: 30 August 2018.