Archosauromorpha ("ruling reptile forms") is a clade of diapsids consisting of all reptiles more closely related to archosaurs than to lepidosaurs. Originating in the middle Permian, they underwent a period of rapid biodiversification in the Triassic.[1]
Evolution[]
Restoration of Marasuchus by Nobu Tamura
Among the earliest definite archosauromorphs belong the polyphyletic clade Protorosauria. Protorosaurus in particular is known from the Wuchiapingian stage of the late Permian;[2] Aenigmastropheus and Eorasaurus are also known from this time.[3] The erect posture found in many extinct archosaurs likely arose prior to the end-Permian mass extinction event as evidenced by chirotheriid ichnotaxa.[3] The Archosauria likely originated immediately before or after the extinction, with the split between Avemetatarsalia and Pseudosuchia occurring at around this time.[3] Poposauroids found in Olenekian strata imply the existence of ghost lineages, suggesting that by the Early Triassic, all main archosaurosauriform lineaages should have been present.[4][5][6] Finally, phylogenetic analyses suggest that the ghost lineages of many archosauromorphs can be extended back into the Permian.[5]
References[]
- ↑ Butler, Richard J.; Scheyer, Torsten M.; Ezcurra, Martín D. (2014-02-27). "The Origin and Early Evolution of Sauria: Reassessing the Permian Saurian Fossil Record and the Timing of the Crocodile-Lizard Divergence". PLOS ONE. 9 (2): e89165. Bibcode:2014PLoSO...989165E. doi:10.1371/journal.pone.0089165. ISSN 1932-6203. PMC 3937355. PMID 24586565.
- ↑ Evans, S. E.; King, M. S. (May 1993). "A new specimen of Protorosaurus (Reptilia: Diapsida) from the Marl Slate (late Permian) of Britain". Proceedings of the Yorkshire Geological Society. 49 (3): 229–234. doi:10.1144/pygs.49.3.229. ISSN 0044-0604.
- ↑ 3.0 3.1 3.2 "Bernardi M, Klein H, Petti FM, Ezcurra MD. The Origin and Early Radiation of Archosauriforms: Integrating the Skeletal and Footprint Record. PLoS One. 2015;10(6):e0128449. Published 2015 Jun 17. doi:10.1371/journal.pone.0128449"
- ↑ Ezcurra MD, Scheyer TM, Butler RJ (2014) The origin and early evolution of Sauria: reassessing the Permian saurian fossil record and the timing of the crocodile-lizard divergence. PLoS ONE 9(2): e89165 10.1371/journal.pone.0089165
- ↑ 5.0 5.1 Nesbitt SJ (2011) The early evolution of archosaurs: relationships and the origin of major clades. Bull Am Mus Nat Hist 352: 1–292.
- ↑ Butler RJ, Brusatte SL, Reich M, Nesbitt SJ, Schoch RR, Hornung JJ. The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation. PLoS One. 2011;6(10):e25693. doi: 10.1371/journal.pone.0025693. Epub 2011 Oct 14. PMID: 22022431; PMCID: PMC3194824.