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Superregnum: Eukaryota
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Cladus: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Cladi: Archosauromorpha – †Choristodera – Lepidosauromorpha
Genera incerta sedis: †Atopodentatus – †Baabdasaurus – †Schilleria
secundum Crawford et al., 2014

Cladus: Sauria
Cladi: ArchelosauriaLepidosauromorpha
secundum Ezcurra, 2016

Cladus: Sauria
Cladi: Archosauromorpha – †Choristodera – Lepidosauromorpha



Crawford, N.G., Parham, J.F., Sellas, A.B., Faircloth, B.C., Glenn, T.C., Papenfuss, T.J., Henderson, J.B., Hansen, M.H. & Simison, W.B. "2015" [2014]. A phylogenomic analysis of turtles. Molecular Phylogenetics and Evolution 83: 250–257. DOI: 10.1016/j.ympev.2014.10.021 PDF Reference page.
Ezcurra, M.D. 2016. The phylogenetic relationships of basal archosauromorphs, with an emphasis on the systematics of proterosuchian archosauriforms. PeerJ 4: e1778. DOI: 10.7717/peerj.1778 Reference page.
Arnold, E.N., Azar, D., Ineich, I. & Nel, A. 2002. The oldest reptile in amber: a 120 million year old lizard from Lebanon. Journal of zoology (London) 258: 7–10. DOI: 10.1017/S0952836902001152
Barabanov, A.V. & Milto, K.D. 2017. An annotated type catalogue of the anguid, dibamid, scincid and varanid lizards in the Department of Herpetology, Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia (Reptilia: Sauria: Anguidae, Dibamidae, Scincidae and Varanidae). Zootaxa 4244(1): 65–78. DOI: 10.11646/zootaxa.4244.1.3. Paywall. Reference page.
Castiglia, R., Annesi, F., Bezerra, A.M.R., Garcia, A.F. & Flores-Villela, O. 2010. Cytotaxonomy and DNA taxonomy of lizards (Squamata, Sauria) from a tropical dry forest in the Chamela-Cuixmala Biosphere Reserve on the coast of Jalisco, Mexico. Zootaxa 2508: 1–29. Preview (PDF).


Sauria – Taxon details on Fossilworks.

Vernacular names
беларуская: Яшчаркі
čeština: Ještěři
Cymraeg: Madfall
Deutsch: Echsen
English: Lizards
español: Saurios
suomi: Liskot
français: Lézards
magyar: Gyíkok
հայերեն: Մողեսներ
italiano: Lucertole
日本語: トカゲ亜目
Nederlands: Hagedissen
norsk: Øgle
polski: Jaszczurki
português: Lagartos
русский: Ящерицы
svenska: Ödlor
ไทย: กิ้งก่า
Türkçe: Kertenkeleler
українська: Ящірки
vèneto: Ligaóra

Sauria is the clade containing the most recent common ancestor of archosaurs (such as crocodilians, dinosaurs, etc.) and lepidosaurs (lizards and kin), and all its descendants.[1] Assuming turtles lie within Sauria, the group can be considered the crown group of diapsids, or reptiles in general.[2] Recent genomic studies[3][4][5] and comprehensive studies in the fossil record[6] suggest that turtles are closely related to archosaurs, not to the pre-Saurian parareptiles as previously thought. Sauria includes all modern reptiles (including birds, a type of archosaur) as well as various extinct groups. Sauria lies within the larger total group Sauropsida, which also contains various stem-reptiles which are more closely related to reptiles than to mammals.[2] Prior to its modern usage, "Sauria" was used as a name for the suborder occupied by lizards, which before 1800 were considered crocodilians.


The synapomorphies or characters that unite the clade Sauria also help them be distinguished from stem-saurians in Diapsida or stem-reptiles in clade Sauropsida in the following categories based on the following regions of the body.[7][8][9]

Cephalad Region
Dorsal origin of temporal musculature
Loss of caniniform region in maxillary tooth row
External nares close to the midline
Postparietal absent
Squamosal mainly restricted to top of skull
The occipital flange of the squamosal is little exposed on the occiput
Anterior process of squamosal narrow
Quadrate exposed laterally
Unossified dorsal process of stapes
Stapes slender
Trunk Region
Sacral ribs oriented laterally
Ontogenetic fusion of caudal ribs
Trunk ribs mostly single headed
Pectoral Region
Cleithrum absent
Pelvic Region
Modified ilium
Limb Region
Tubular bone lost
Entepicondylar foramen absent
Radius as long as ulna
Small proximal carpals and tarsal
Fifth distal tarsal absent
Short and stout fifth or hooked metatarsal
Perforating foramen of manus lost

However, some of these characters might be lost or modified in several lineages, particularly among birds and turtles; it is best to see these characters as the ancestral features that were present in the ancestral saurian.[7]

The cladogram shown below follows the most likely result found by an analysis of turtle relationships using both fossil and genetic evidence by M.S. Lee, in 2013. This study found Eunotosaurus, usually regarded as a turtle relative, to be only very distantly related to turtles in the clade Parareptilia.[6]


Araeoscelidia Spinoaequalis schultzei reconstruction flipped.jpg


Claudiosaurus Claudiosaurus white background.jpg

Younginiformes Hovasaurus BW flipped.jpg


LepidosauromorphaZoology of Egypt (1898) (Varanus griseus).png


ChoristoderaHyphalosaurus mmartyniuk wiki flipped.png

Prolacertiformes Prolacerta broomi.jpg

TrilophosaurusTrilophosaurus buettneri (flipped).jpg

RhynchosauriaHyperodapedon BW2 white background.jpg

ArchosauriformesDescription des reptiles nouveaux, ou, Imparfaitement connus de la collection du Muséum d'histoire naturelle et remarques sur la classification et les caractères des reptiles (1852) (Crocodylus moreletii).jpg


EosauropterygiaDolichorhynchops BW flipped.jpg

PlacodontiaPsephoderma BW flipped.jpg





TestudinesPsammobates geometricus 1872 white background.jpg


The cladogram below follows the most likely result found by another analysis of turtle relationships, this one using only fossil evidence, published by Rainer Schoch and Hans-Dieter Sues in 2015. This study found Eunotosaurus to be an actual early stem-turtle, though other versions of the analysis found weak support for it as a parareptile.[10]
TestudinesPsammobates geometricus 1872 white background.jpg



ArchosauromorphaDescription des reptiles nouveaux, ou, Imparfaitement connus de la collection du Muséum d'histoire naturelle et remarques sur la classification et les caractères des reptiles (1852) (Crocodylus moreletii).jpgMeyers grosses Konversations-Lexikon - ein Nachschlagewerk des allgemeinen Wissens (1908) (Antwerpener Breiftaube).jpg


KuehneosauridaeIcarosaurus white background.jpg


SquamataZoology of Egypt (1898) (Varanus griseus).png

RhynchocephaliaHatteria white background.jpg


EosauropterygiaDolichorhynchops BW flipped.jpg


PlacodontiaPsephoderma BW flipped.jpg


PappochelysBild2 Ur-Schildkröte Zeichnung.jpg




TestudinesPsammobates geometricus 1872 white background.jpg



Gauthier, J. A., Kluge, A. G., & Rowe, T. (1988). The early evolution of the Amniota. The phylogeny and classification of the tetrapods, 1, 103-155.
Ezcurra, M. D.; Scheyer, T. M.; Butler, R. J. (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. doi:10.1371/journal.pone.0089165. PMC 3937355. PMID 24586565.
Wang, Zhuo (27 March 2013). "The draft genomes of soft-shell turtle and green sea turtle yield insights into the development and evolution of the turtle-specific body plan". Nature Genetics. 45 (701–706): 701–6. doi:10.1038/ng.2615. PMC 4000948. PMID 23624526.
Crawford, Nicholas G., et al. "More than 1000 ultraconserved elements provide evidence that turtles are the sister group of archosaurs." Biology letters 8.5 (2012): 783-786.
Jarvis, E.D.; et al. (2014). "Whole-genome analyses resolve early branches in the tree of life of modern birds". Science. 346 (6215): 1320–1331. doi:10.1126/science.1253451. PMC 4405904. PMID 25504713.
Lee, M. S. Y. (2013). "Turtle origins: Insights from phylogenetic retrofitting and molecular scaffolds". Journal of Evolutionary Biology. 26 (12): 2729–2738. doi:10.1111/jeb.12268. PMID 24256520. S2CID 2106400.
Pough, F. H., Janis, C. M., & Heiser, J. B. (2005). Vertebrate life. Pearson/Prentice Hall.
Laurin, Michel and Jacques A. Gauthier. 2011. Diapsida. Lizards, Sphenodon, crocodylians, birds, and their extinct relatives. Version 20 April 2011. in The Tree of Life Web Project,
Laurin, Michel and Jacques A. Gauthier. 2011. Autapomorphies of Diapsid Clades. Version 20 April 2011. in The Tree of Life Web Project,
Schoch, Rainer R.; Sues, Hans-Dieter (24 June 2015). "A Middle Triassic stem-turtle and the evolution of the turtle body plan". Nature. 523 (7562): 584–587. doi:10.1038/nature14472. PMID 26106865. S2CID 205243837.

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