Stereospondylomorpha

Restoration of Benthosuchus sushkini, from here.

Belongs within: Temnospondyli.
Contains: Trematosauria.

The Stereospondylomorpha are a group of mostly aquatic temnospondyls known from the early Permian to early Cretaceous, though their diversity was much reduced after the end of the Triassic. They include the Permian Archegosauroidea, species of which were superficially crocodile-like with long narrow snouts.

Synapomorphies (from Yates & Warren 2000): Jugal extending anterior to orbit; prefrontal-jugal suture present; maxilla-nasal suture present; arcadian groove present on post glenoid area of mandible.

<==Stereospondylomorpha YW00
    |--Archegosauroidea YW00
    |    |  i. s.: Bageherpeton Dias & Barberena 2001 D07
    |    |           `--B. longignathus D07
    |    |--Actinodontidae YW00
    |    |    |--Cheliderpeton latirostre YW00
    |    |    `--Sclerocephalus [incl. Actinodon] YW00
    |    |         `--S. haeuseri YW00
    |    `--Archegosauridae YW00
    |         |--Melosauridae TT05
    |         |    |--Konzhukovia vetusta (Konzhukova 1955) YW00, TT05
    |         |    |--Tryphosuchus kinelensis (V’yushkov 1955) TT05
    |         |    `--Uralosuchus tverdochlebovae Gubin 1993 TT05
    |         `--+--Archegosaurus decheni YW00
    |            `--Platyoposaurus YW00
    |                 |--P. rickardi (Twelvetrees 1880) TT05
    |                 |--P. stuckenbergi YW00
    |                 `--P. vjuschkovi Gubin 1989 TT05
    `--Stereospondyli YW00
         |  i. s.: Aphaneramma S02
         |         Dutuitosaurus ouazzoui S02
         |         Kupferzellia S02
         |--Peltobatrachus Panchen 1959 YW00, D07
         |    `--P. pustulatus YW00
         `--+--Lapillopsis nana YW00
            `--+--Rhinesuchidae YW00
               |    |--Rhinesuchus PS88
               |    |--Rhineceps YW00
               |    `--Uranocentrodon [Uranocentrodontidae] YW00
               |         `--U. senekalensis (Van Hoepen 1911) CZ79
               `--+--Trematosauria YW00
                  `--Capitosauria [Capitosauroidei] YW00
                       |--+--Chomatobatrachus YW00
                       |  `--Lydekkerinidae CZ79
                       |       |--Limnoiketes paludinatans Parrington 1948 CZ79
                       |       |--Cryobatrachus kitchingi CZ79
                       |       `--Lydekkerina YW00
                       |            |--L. huxleyi (Lydekker 1889) (see below for synonymy) CZ79
                       |            `--L. kitchingi Broom 1950 CZ79
                       `--Capitosauroidea YW00
                            |--Mastodonsauridae
                            |    |--Heptasaurus cappelensis (Wepfer 1923) S02
                            |    `--Mastodonsaurus Jaeger 1828 YW00, D07
                            |         |--M. cappelensis D07
                            |         |--M. giganteus S02
                            |         |--M. lavisi SS02
                            |         |--M. robustus F71 [=Capitosaurus robustus S87]
                            |         `--M. torvus D07
                            `--Capitosauridae YW00
                                 |--Paracyclotosaurus davidi Watson 1958 YW00, F71
                                 |--Kestrosaurus dreyeri Haughton 1925 CZ79
                                 |--Parotosaurus peabodyi CZ79
                                 |--Parotosuchus YW00
                                 |    |--P. aliciae YW00
                                 |    `--P. gunganj YW00
                                 `--Benthosuchus CZ79
                                      |--B. korobkovi S02
                                      |--B. sushkini YW00
                                      `--B. uralensis S02

Inorganic: Mastodonsaurus minirotundomaculosus Okamura 1987 O87
           Benthosuchus sushkini minilorientalus Okamura 1987 O87

Lydekkerina huxleyi (Lydekker 1889) [incl. L. dutoiti Broom 1930, Broomulus dutoiti, L. putterilli Broom 1930, Putterillia platyceps Broom 1930] CZ79

*Type species of generic name indicated

REFERENCES

[CZ79] Cosgriff, J. W., & J. M. Zawiskie. 1979. A new species of the Rhytidosteidae from the Lystrosaurus Zone and a review of the Rhytidosteoidea. Palaeontologia Africana 22: 1–27.

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

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

[O87] Okamura, C. 1987. New facts: Homo and all Vertebrata were born simultaneously in the former Paleozoic in Japan. Original Report of the Okamura Fossil Laboratory 15: 347–573.

[PS88] Panchen, A. L., & T. R. Smithson. 1988. The relationships of the earliest tetrapods. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 1. Amphibians, Reptiles, Birds pp. 1–32. Clarendon Press: Oxford.

[S02] Schoch, R. R. 2002. The neurocranium of the stereospondyl Mastodonsaurus giganteus. Palaeontology 45 (3): 627–645.

[SS02] Spencer, P. S., & G. W. Storrs. 2002. A re-evaluation of small tetrapods from the Middle Triassic Otter Sandstone Formation of Devon, England. Palaeontology 45 (3): 447–467.

[S87] Stephens, W. J. 1887. On the Biloela labyrinthodont (second notice). Proceedings of the Linnean Society of New South Wales, series 2, 1 (4): 1113–1121, pl. 14.

[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.

[YW00] Yates, A. M., & A. A. Warren. 2000. The phylogeny of the ‘higher’ temnospondyls (Vertebrata: Choanata) and its implications for the monophyly and origins of the Stereospondyli. Zoological Journal of the Linnean Society 128: 77–121.

Last updated: 3 August 2017.