Fossil skeleton of Labidosaurus hamatus, photographed by Ghedoghedo.

Belongs within: Reptilia.

The Captorhinidae were a family of Permian reptiles, members of which include the oldest known herbivorous reptiles. Some of these herbivorous forms became relatively large, and two lineages evolved multiple marginal tooth rows (Modesto et al. 2007). The early genus Romeria, including two species from the lower Permian of Texas, was more plesiomorphic than other captorhinids and was classified by various earlier authors with members of a similar basal reptile family, the Protorothyrididae.

Synapomorphies (from Modesto et al. 2007): Premaxilla with ventral margin aligned anteroventrally in lateral aspect, alary process present on posterodorsal process; maxilla with posterior end flexed laterally in ventral aspect; premaxillary dentition with first tooth subequal to maxillary caniniforms; maxillary dentition with 25 or less tooth positions.

<==Captorhinidae [Captorhina]
    |  i. s.: Captorhinikos parvus M96
    |         Captorhinoides LR95
    |         Hecatogomphius LR95
    |         Kahneria LR95
    |         Moradisaurus grandis MS07
    |         Rothianiscus LR95
    |--Romeria MS07
    |    |--R. prima Clark & Carroll 1973 MS07
    |    `--R. texana Price 1937 MS07
    `--+--Protocaptorhinus pricei MS07
       `--+--Rhiodenticulatus heatoni MS07
          `--+--Saurorictus Modesto & Smith 2001 MS07, MS01
             |    `--*S. australis Modesto & Smith 2001 MS01
             `--+--Captorhinus Cope 1918 MS07, D07
                |    |--C. laticeps [=Eocaptorhinus laticeps; incl. Labidosaurus oklahomensis Seltin 1959] MS07
                |    `--+--C. aguti Cope 1882 MS07, RCQ03 [=Eocaptorhinus aguti GM88]
                |       `--C. magnus MS07
                `--+--Labidosaurikos meachami MS07
                   `--Labidosaurus Cope 1896 MS07
                        `--*L. hamatus (Cope 1895) [incl. L. broilii Case 1911] MS07

*Type species of generic name indicated


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

[GM88] Gaffney, E. S., & P. A. Meylan. 1988. A phylogeny of turtles. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 1. Amphibians, Reptiles, Birds pp. 157–219. Clarendon Press: Oxford.

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

[M96] Modesto, S. P. 1996. A basal captorhinid reptile from the Fort Sil fissures, Lower Permian of Oklahoma. Oklahoma Geology Notes 56 (1): 4–14.

[MS07] Modesto, S. P., D. M. Scott, D. S. Berman, J. Müller & R. R. Reisz. 2007. The skull and the paleoecological significance of Labidosaurus hamatus, a captorhinid reptile from the Lower Permian of Texas. Zoological Journal of the Linnean Society 149 (2): 237–262.

[MS01] Modesto, S. P., & R. M. H. Smith. 2001. A new Late Permian captorhinid reptile: a first record from the South African Karoo. Journal of Vertebrate Paleontology 21 (3): 405–409.

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

Last updated: 17 July 2018.

1 comment:

  1. The Captorhinida, as many other Carboniferous and Permian groups, are basal ammniotes, but not reptiles.


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