Eureptilia

Eureptilia ("true reptiles") is one of the two major subgroups of the clade Sauropsida, the other one being Parareptilia. Eureptilia includes Diapsida (the clade containing all modern reptiles and birds), as well as a number of primitive Permo-Carboniferous forms previously classified under Anapsida, in the old (no longer recognised) order "Cotylosauria".^[2]

Eureptiles Temporal range: Late Carboniferous–Present[1] PreꞒ Ꞓ O S D C P T J K Pg N
Labidosaurikos meachami, an early eureptilian of the family Captorhinidae
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Eureptilia Olson, 1947
Subgroups
†Hylonomus †Thuringothyris †Captorhinidae †"Protorothyrididae" Diapsida

Skull of Hylonomus, a eureptile and one of the oldest known reptiles

Eureptilia is characterized by the skull having greatly reduced supraoccipital, tabular, and supratemporal bones that are no longer in contact with the postorbital. Aside from Diapsida, the group notably contains Captorhinidae, a diverse and long lived (Late Carboniferous-Late Permian) clade of initially small carnivores that later evolved into large herbivores.^[3] Other primitive eureptiles such as the "protorothyrids" were all small, superficially lizard-like forms, that were probably insectivorous.^[4] One primitive eureptile, the Late Carboniferous "protorothyrid" Anthracodromeus, is the oldest known climbing tetrapod.^[5] Diapsids were the only eureptilian clade to continue beyond the end of the Permian.

Classification

Eureptilia was defined as a stem-based clade, specifically, the most inclusive clade containing Captorhinus aguti and Petrolacosaurus kansensis but not Procolophon trigoniceps, by Tsuji and Müller (2009).^[6] The cladogram here was modified after Muller and Reisz (2006):^[7]

Reptilia	†Parareptilia  Eureptilia  †Coelostegus †Thuringothyris †Captorhinidae †Brouffia †Paleothyris †Hylonomus †Anthracodromeus †Cephalerpeton †Protorothyris Diapsida

References

1. Marjanović, D. (2021). "The Making of Calibration Sausage Exemplified by Recalibrating the Transcriptomic Timetree of Jawed Vertebrates". Frontiers in Genetics. 12. 521693. doi:10.3389/fgene.2021.521693. PMC 8149952. PMID 34054911.
2. Simões, T. R.; Kammerer, C. F.; Caldwell, M. W.; Pierce, S. E. (2022). "Successive climate crises in the deep past drove the early evolution and radiation of reptiles". Science Advances. 8 (33): eabq1898. doi:10.1126/sciadv.abq1898. PMC 9390993. PMID 35984885.
3. Brocklehurst, Neil (2017-04-13). "Rates of morphological evolution in Captorhinidae: an adaptive radiation of Permian herbivores". PeerJ. 5: e3200. doi:10.7717/peerj.3200. ISSN 2167-8359. PMC 5392250. PMID 28417061.
4. Canoville, Aurore; Laurin, Michel (2010-05-19). "Evolution of humeral microanatomy and lifestyle in amniotes, and some comments on palaeobiological inferences: AMNIOTE MICROANATOMY AND PALAEOBIOLOGICAL INFERENCE". Biological Journal of the Linnean Society. 100 (2): 384–406. doi:10.1111/j.1095-8312.2010.01431.x.
5. Mann, Arjan; Dudgeon, Thomas W.; Henrici, Amy C.; Berman, David S; Pierce, Stephanie E. (2021). "Digit and Ungual Morphology Suggest Adaptations for Scansoriality in the Late Carboniferous Eureptile Anthracodromeus longipes". Frontiers in Earth Science. 9: 440. Bibcode:2021FrEaS...9..440M. doi:10.3389/feart.2021.675337. ISSN 2296-6463.
6. Benton, M. J., Donoghue, P. C., Asher, R. J., Friedman, M., Near, T. J., & Vinther, J. (2015). "Constraints on the timescale of animal evolutionary history." Palaeontologia Electronica, 18.1.1FC; 1-106; palaeo-electronica.org/content/fc-1
7. Muller, J. and Reisz, R.R. (2006). "The phylogeny of early eureptiles: Comparing parsimony and Bayesian approaches in the investigation of a basal fossil clade." Systematic Biology, 55(3):503-511. doi:10.1080/10635150600755396

External links

• Eureptilia examples of some Permian species
• Eureptilia