Slavoiais an extinct genus oflizardfrom theEarly CretaceousofMongolia(Dzunbain Formation[1]), andLate CretaceousofKazakhstan(Bostobe Formation[2]) andMongolia(Barun Goyot FormationandDjadochta Formation).
| Slavoia | |
|---|---|
| |
| ZPAL MgR-I/8, theholotypespecimen | |
Scientific classification
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Family: | †Slavoiidae |
| Genus: | †Slavoia Sulimski, 1984 |
| Type species | |
| †Slavoia darevskii Sulimski, 1984
| |
There is only a single speciesS. darevskii,[3]andSlavoiahas been suggested to be the oldest known relative ofamphisbaenians.
Description
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The structure of theskullofSlavoiasuggests that it may have had afossorial(burrowing) lifestyle,[4][5]and when fully grown, it likely grew up to 12 centimetres (4.7 in) long.[6]
Slavoiais known from several specimens including the holotype ZPAL MgR-I/8,[3]mostly made up of incomplete skulls and skeletons, and it has therefore been possible to reconstruct its appearance.[5]Slavoiais characterized by a skull with a very compact structure, and the orbits were small, the parietal hole was small or non-existent. The teeth, pleurodonts, were robust. The premaxilla had five teeth, while the maxilla and jaw had seven or eight. The lacrimal bone was greatly reduced, and there were 26 presacral vertebrae, equipped with an anteriorly hollow vertebral centre (procelus).[3]Relative to most lizards, the limbs were relatively small, and the body was elongated, suggested to be adaptations for a burrowing lifestyle. The firstdigitof the hand had hyperphalangy (the presence of additionalphalangebones).[5]
Classification
editAlifanov (1993), Gao and Norell (2000), Kearney (2003) and Bolet et al. (2022) placedSlavoiawithinScincomorpha.[7][8][9][10]Conrad (2008) placed in a clade containingLacertoidea+Scincomorpha.[11]Tałanda (2016, 2017), who provided a new description of the genus, placed it as a stem-group relative ofamphisbaenianswithin Lacertoidea.[12][5]
References
edit- ^Alifanov V. R. (2000) The fossil record of Cretaceous lizards from Mongolia,The Age of Dinosaurs in Russia and Mongolia,368-389
- ^Kordikova, E. G.; Polly, P. D.; Alifanov, V. A.; Roček, Z.; Gunnell, G. F.; Averianov, A. O. (March 2001)."Small vertebrates from the late Cretaceous and early Tertiary of the northeastern Aral Sea region, Kazakhstan".Journal of Paleontology.75(2): 390–400.doi:10.1017/s0022336000018187.ISSN0022-3360.
- ^abcSulimski, A. (1984). A new Cretaceous scincomorph lizard from Mongolia.Palaeontologia Polonica46:143-155
- ^Tałanda, Mateusz (2015)."Cretaceous roots of the amphisbaenian lizards".Zoologica Scripta.45(1): 1–8.doi:10.1111/zsc.12138.ISSN0300-3256.S2CID85570915.
- ^abcdTałanda, Mateusz (2017)."Evolution of postcranial skeleton in worm lizards inferred from its status in the Cretaceous stem-amphisbaenianSlavoia darevskii".Acta Palaeontologica Polonica.62.doi:10.4202/app.00294.2016.ISSN0567-7920.
- ^"Slavoia".Nix Illustration.Retrieved5 September2023.
- ^Alifanov, Vladimir. (1993). Some peculiarities of the Cretaceous and Palaeogene lizard faunas of the Mongolian People's Republic.Kaupia.3. 9-13.
- ^Gao, K.-Q. M. A. Norell. (2000) Taxonomic composition and systematics of Late Cretaceous lizard assemblages from Ukhaa Tolgod and adjacent localities, Mongolian Gobi Desert."Bulletin of the American Museum of Natural History".249, s. 1-118,
- ^Kearney, M. (2003) The phylogenetic position of Sineoamphisbaena hexatabularis reexamined."Journal of Vertebrate Paleontology".23, s. 394-403,
- ^Bolet, Arnau; Stubbs, Thomas L; Herrera-Flores, Jorge A; Benton, Michael J (2022-05-03). Zhu, Min; Perry, George H; Zhu, Min (eds.)."The Jurassic rise of squamates as supported by lepidosaur disparity and evolutionary rates".eLife.11:e66511.doi:10.7554/eLife.66511.ISSN2050-084X.PMC9064307.PMID35502582.
- ^Conrad, J. L.. (2008) Phylogeny and systematics of Squamata (Reptilia) based on morphology."Bulletin of the American Museum of Natural History".310, s. 1-182,
- ^Tałanda, Mateusz (January 2016)."Cretaceous roots of the amphisbaenian lizards".Zoologica Scripta.45(1): 1–8.doi:10.1111/zsc.12138.ISSN0300-3256.S2CID85570915.