Pareiasauria

Last updated

Pareiasauria
Temporal range: Middle Permian - Late Permian, 265–252  Ma
Scutosaurus.jpg
Skeleton of Scutosaurus karpinskii in the American Museum of Natural History
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Parareptilia
Order: Procolophonomorpha
Node: Ankyramorpha
Suborder: Procolophonia
Clade: Pareiasauromorpha
Superfamily: Pareiasauroidea
Clade: Pareiasauria
Seeley, 1888
Genera

Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with osteoderms which covered large areas of the body. They first appeared in southern Pangea during the Middle Permian, before becoming globally distributed during the Late Permian. Pareiasaurs were the largest reptiles of the Permian, reaching sizes equivalent to those of contemporary therapsids. Pareiasaurs became extinct in the Permian–Triassic extinction event.

Contents

Description

Restoration of Bradysaurus Bradysaurus BW.jpg
Restoration of Bradysaurus

Pareiasaurs ranged in size from 60 to 300 centimetres (2.0 to 9.8 ft) long, with some species estimated to exceed 1,000 kilograms (2,200 lb) in body mass. [1] [2] The limbs of many parieasaurs were extremely robust, likely to account for the increased stress on their limbs caused by their typically sprawling posture. [1] [2] The cow-sized Bunostegos differed from other pareiasaurs by having a more upright limb posture, being amongst the first amniotes to develop this trait. [3] Pareiasaurs were protected by bony scutes called osteoderms that were set into the skin. [4] Their skulls were heavily ornamented with bosses, rugose ridges, and bumps. [5] Their leaf-shaped multi-cusped teeth resemble those of iguanas, indicating a herbivorous diet. [6] The body probably housed an extensive digestive tract. [1] Most authors have assumed a terrestrial lifestyle for pareiasaurs. A 2008 bone microanatomy study suggested a more aquatic, plausibly amphibious lifestyle, [7] but a later 2019 study found that the bone histology provided no direct evidence of this lifestyle. [8]

Evolutionary history

Pareiasaurs appear very suddenly in the fossil record. It is clear that these animals are parareptiles. [9] [10] As such, they are closely related to nycteroleterids. [11] Pareiasaurs filled the large herbivore niche (or guild) that had been occupied early in the Permian period by the caseid pelycosaurs and, before them, the diadectid reptiliomorphs. [8] They are much larger than the diadectids, more similar to the giant caseid pelycosaur Cotylorhynchus . Although the last Pareiasaurs were no larger than the first types (indeed, many of the last ones became smaller), there was a definite tendency towards increased armour as the group developed. Pareiasaurs first appeared in the fossil record in the Middle Permian (Guadalupian) of Southern Pangaea, before dispersing into Northern Pangaea and gaining a cosmopolitan distribution during the Late Permian (Lopingian). [12]

Classification

Some paleontologists considered that pareiasaurs were direct ancestors of modern turtles. Pareiasaur skulls have several turtle-like features, and in some species the scutes have developed into bony plates, possibly the precursors of a turtle shell. [13] Jalil and Janvier, in a large analysis of pareiasaur relationships, also found turtles to be close relatives of the "dwarf" pareiasaurs, such as Pumiliopareia . [14] However, the discovery of Pappochelys argues against a potential pareisaurian relationship to turtles, [15] and DNA evidence indicates that living turtles are more closely related to living archosaurs than lepidosaurs, and therefore cladistically diapsids. [16]

Associated clades

Hallucicrania (Lee 1995): This clade was coined by MSY Lee for Lanthanosuchidae + (Pareiasauridae + Testudines). Lee's pareiasaur hypothesis has become untenable due to the diapsid features of the stem turtle Pappochelys and the potential testudinatan nature of Eunotosaurus . Recent cladistic analyses reveal that lanthanosuchids have a much more basal position in the Procolophonomorpha, and that the nearest sister taxon to the pareiasaurs are the rather unexceptional and conventional looking nycteroleterids (Müller & Tsuji 2007, Lyson et al. 2010) the two being united in the clade Pareiasauromorpha (Tsuji et al. 2012).

Pareiasauroidea (Nopcsa, 1928): This clade (as opposed to the superfamily or suborder Pareiasauroidea) was used by Lee (1995) for Pareiasauridae + Sclerosaurus. More recent cladistic studies place Sclerosaurus in the procolophonid subfamily Leptopleuroninae (Cisneros 2006, Sues & Reisz 2008), which means the similarities with pareiasaurs are the result of convergences.

Pareiasauria (Seeley, 1988): If neither Lanthanosuchidae or Testudines are included in the clade, the Pareiasauria only contains the monophyletic family Pareiasauridae.

Phylogeny

Below is a cladogram from Tsuji et al. (2013): [17]

Pareiasauria

Related Research Articles

<span class="mw-page-title-main">Mesosaur</span> Extinct family of reptiles

Mesosaurs were a group of small aquatic reptiles that lived during the early Permian period (Cisuralian), roughly 299 to 270 million years ago. Mesosaurs were the first known aquatic reptiles, having apparently returned to an aquatic lifestyle from more terrestrial ancestors. It is uncertain which and how many terrestrial traits these ancestors displayed; recent research cannot establish with confidence if the first amniotes were fully terrestrial, or only amphibious. Most authors consider mesosaurs to have been aquatic, although adult animals may have been amphibious, rather than completely aquatic, as indicated by their moderate skeletal adaptations to a semiaquatic lifestyle. Similarly, their affinities are uncertain; they may have been among the most basal sauropsids or among the most basal parareptiles.

<i>Scutosaurus</i> Extinct genus of reptiles

Scutosaurus is an extinct genus of pareiasaur parareptiles. Its genus name refers to large plates of armor scattered across its body. It was a large anapsid reptile that, unlike most reptiles, held its legs underneath its body to support its great weight. Fossils have been found in the Sokolki Assemblage Zone of the Malokinelskaya Formation in European Russia, close to the Ural Mountains, dating to the late Permian (Lopingian) between 264 and 252 million years ago.

<span class="mw-page-title-main">Parareptilia</span> Extinct subclass of reptiles (306–201Ma ago)

Parareptilia ("near-reptiles") is an extinct subclass or clade of basal sauropsids/reptiles, typically considered the sister taxon to Eureptilia. Parareptiles first arose near the end of the Carboniferous period and achieved their highest diversity during the Permian period. Several ecological innovations were first accomplished by parareptiles among reptiles. These include the first reptiles to return to marine ecosystems (mesosaurs), the first bipedal reptiles, the first reptiles with advanced hearing systems, and the first large herbivorous reptiles. The only parareptiles to survive into the Triassic period were the procolophonoids, a group of small generalists, omnivores, and herbivores. The largest family of procolophonoids, the procolophonids, rediversified in the Triassic, but subsequently declined and became extinct by the end of the period.

<i>Elginia</i> Extinct genus of reptiles

Elginia is an extinct genus of pareiasaurid known from the Late Permian of Scotland and China. It was named for the area around Elgin in Scotland, which has yielded many fossils referred to as the Elgin Reptiles.

<span class="mw-page-title-main">Procolophonia</span> Extinct suborder of reptiles

Procolophonia is an extinct suborder (clade) of herbivorous reptiles that lived from the Middle Permian till the end of the Triassic period. They were originally included as a suborder of the Cotylosauria but are now considered a clade of Parareptilia. They are closely related to other generally lizard-like Permian reptiles such as the Millerettidae, Bolosauridae, Acleistorhinidae, and Lanthanosuchidae, all of which are included under the Anapsida or "Parareptiles".

<span class="mw-page-title-main">Procolophonomorpha</span> Order of reptiles (fossil)

Procolophonomorpha is an order or clade containing most parareptiles. Many papers have applied various definitions to the name, though most of these definitions have since been considered synonymous with modern parareptile clades such as Ankyramorpha and Procolophonia. The current definition of Procolophonomorpha, as defined by Modesto, Scott, & Reisz (2009), is that of as a stem-based group containing Procolophon and all taxa more closely related to it than to Milleretta. It constitutes a diverse assemblage that includes a number of lizard-like forms, as well as more diverse types such as the pareiasaurs. Lee 1995, 1996, 1997 argues that turtles evolved from pareiasaurs, but this view is no longer considered likely. Rieppel and deBraga 1996 and deBraga and Rieppel, 1997 argue that turtles evolved from sauropterygians, and there is both molecular and fossil (Pappochelys) evidence for the origin of turtles among diapsid reptiles.

<i>Nyctiphruretus</i> Extinct genus of reptiles

Nyctiphruretus is an extinct genus of nyctiphruretid parareptile known from the Guadalupian series of European Russia.

<i>Eunotosaurus</i> Extinct genus of reptiles

Eunotosaurus is an extinct genus of amniote, possibly a close relative of turtles. Eunotosaurus lived in the late Middle Permian and fossils can be found in the Karoo Supergroup of South Africa. Eunotosaurus resided in the swamps of what is now southern Africa. Its ribs were wide and flat, forming broad plates similar to a primitive turtle shell, and the vertebrae were nearly identical to those of some turtles. Accordingly, it is often considered as a possible transitional fossil between turtles and their prehistoric ancestors. However, it is possible that these turtle-like features evolved independently of the same features in turtles, since other anatomical studies and phylogenetic analyses suggest that Eunotosaurus may instead have been a parareptile, an early-diverging neodiapsid unrelated to turtles, or a synapsid.

<span class="mw-page-title-main">Acleistorhinidae</span> Extinct family of reptiles

Acleistorhinidae is an extinct family of Late Carboniferous and Early Permian-aged parareptiles. Acleistorhinids are most diverse from the Richards Spur locality of the Early Permian of Oklahoma. Richards Spur acleistorhinids include Acleistorhinus, Colobomycter, and possibly Delorhynchus and Feeserpeton. Other taxa include Carbonodraco from the Late Carboniferous of Ohio and Karutia from the Early Permian of Brazil. Acleistorhinidae is commonly considered a subgroup of lanthanosuchoids, related to taxa such as Chalcosaurus, Lanthaniscus and Lanthanosuchus. However, a re-examination of parareptile phylogeny conducted by Cisneros et al. (2021) argued that lanthanosuchids were not closely related to acleistorhinids. The phylogenetic analysis conducted by these authors recovered acleistorhinids as the sister group of the clade Procolophonia, while lanthanosuchids were recovered within the procolophonian subgroup Pareiasauromorpha.

<i>Acleistorhinus</i> Extinct genus of reptiles

Acleistorhinus (ah-kles-toe-RYE-nuss) is an extinct genus of parareptile known from the Early Permian of Oklahoma. It is notable for being the earliest known anapsid reptile yet discovered. The morphology of the lower temporal fenestra of the skull of Acleistorhinus bears a superficial resemblance to that seen in early synapsids, a result of convergent evolution. Only a single species, A. pteroticus, is known, and it is classified in the Family Acleistorhinidae, along with Colobomycter.

<i>Microleter</i> Extinct genus of reptiles

Microleter is an extinct genus of basal procolophonomorph parareptiles which lived in Oklahoma during the Early Permian period. The type and only known species is Microleter mckinzieorum. Microleter is one of several parareptile taxa described from the Richards Spur fissure fills, and can be characterized from its high tooth count, lacrimal/narial contact, short postfrontal, and slit-like temporal emargination edged by the postorbital, jugal, squamosal, and quadratojugal. Contrary to Australothyris, which had a similar phylogenetic position as a basal procolophonomorph, Microleter suggests that early parareptile evolution occurred in Laurasia and that multiple lineages developed openings or emarginations in the temporal region.

<span class="mw-page-title-main">Velosauria</span> Extinct clade of reptiles

Velosauria is a group of pareiasaur reptiles that existed in the late Permian period. They ranged in size from the 50-centimeter-long Pumiliopareia to the 3-meter-long Scutosaurus. Velosaurs were some of the largest reptiles of their time.

<span class="mw-page-title-main">Ankyramorpha</span> Extinct clade of reptiles

Ankyramorpha is an extinct clade of procolophonomorph parareptiles which lived between the early Cisuralian epoch and the latest Triassic period of Africa, Antarctica, Asia, Australia, Europe, North America and South America.

<span class="mw-page-title-main">Lanthanosuchoidea</span> Extinct superfamily of reptiles

Lanthanosuchoidea is an extinct superfamily of ankyramorph parareptiles from the middle Pennsylvanian to the middle Guadalupian epoch of Europe, North America and Asia. It was named by the Russian paleontologist Ivachnenko in 1980, and it contains two families Acleistorhinidae and Lanthanosuchidae.

Nyctiphruretidae is an extinct family of hallucicranian parareptiles known from the late Early to the late Middle Permian of European Russia and south-central United States.

<i>Bunostegos</i> Genus of reptiles (fossil)

Bunostegos is an extinct genus of pareiasaur parareptile from the Late Permian of the Agadez Region in Niger. The type species, Bunostegos akokanensis, was named from the Moradi Formation in 2003. It was a cow-sized animal with a distinctive skull that had large bony knobs, similar in form to those of other pareiasaurs but far larger. The species appears to have lived in a desert in the centre of the supercontinent of Pangaea.

<span class="mw-page-title-main">Nycteroleteridae</span> Extinct family of reptiles

Nycteroleteridae is a family of procolophonian parareptilians from the Middle to Late Permian of Russia and North America. They are sometimes classified as a sister group to pareiasaurids. The group includes the genera Macroleter, Bashkyroleter, "Bashkyroleter" mesensis, Nycteroleter, Emeroleter, and probably Rhipaeosaurus. They were carnivorous, and occasionally ate insects. The group was most common in European Russia, with only a few fossils in North America. One fossil has also been found in Africa, but this is the only one from Gondwana.

<span class="mw-page-title-main">Pareiasauromorpha</span> Extinct clade of reptiles

Pareiasauromorpha is a group of parareptilian amniotes from the Permian. It includes genera found all over the world, with many genera from Asia and South Africa. The clade was first used as a group by Linda A. Tsuji in 2011, in order to group the family Nycteroleteridae (nycteroleters) and the superfamily Pareiasauroidea (pareiasaurs). Pareiasauromorpha is considered to be a monophyletic node, the sister group to procolophonoids.

<span class="mw-page-title-main">Pantestudines</span> Clade of reptiles

Pantestudines or Pan-Testudines is the proposed group of all reptiles more closely related to turtles than to any other living animal. It includes both modern turtles and all of their extinct relatives. Pantestudines with a complete shell are placed in the clade Testudinata.

<i>Parasaurus</i> Extinct genus of reptiles

Parasaurus is a genus of pareiasaur known from fossils collected in the Kupferschiefer in Germany, dating to the Late Permian (Wuchiapingian). The type species, Parasaurus geinitzi, described by Hermann von Meyer in 1857, was the first pareiasaur ever described. The seven known specimens were redescribed in 2008.

References

  1. 1 2 3 Romano, Marco; Manucci, Fabio; Rubidge, Bruce; Van den Brandt, Marc J. (2021-06-17). "Volumetric Body Mass Estimate and in vivo Reconstruction of the Russian Pareiasaur Scutosaurus karpinskii". Frontiers in Ecology and Evolution. 9: 692035. doi: 10.3389/fevo.2021.692035 . hdl: 11573/1634310 . ISSN   2296-701X.
  2. 1 2 Van den Brandt, Marc Johan; Day, Michael Oliver; Manucci, Fabio; Viglietti, Pia Alexa; Angielczyk, Kenneth David; Romano, Marco (2023-02-27). "First volumetric body mass estimate and a new in vivo 3D reconstruction of the oldest Karoo pareiasaur Bradysaurus baini, and body size evolution in Pareiasauria". Historical Biology: 1–15. doi:10.1080/08912963.2023.2175211. ISSN   0891-2963. S2CID   257369904.
  3. Turner, Morgan L.; Tsuji, Linda A.; Ide, Oumarou; Sidor, Christian A. (2015-11-02). "The vertebrate fauna of the upper Permian of Niger—IX. The appendicular skeleton of Bunostegos akokanensis (Parareptilia: Pareiasauria)". Journal of Vertebrate Paleontology. 35 (6): e994746. Bibcode:2015JVPal..35E4746T. doi:10.1080/02724634.2014.994746. ISSN   0272-4634. S2CID   86503874.
  4. Scheyer, T. M. & Sander, P. M. (2009). "Bone microstructures and mode of skeletogenesis in osteoderms of three pareiasaur taxa from the Permian of South Africa". Journal of Evolutionary Biology. 22 (6): 1153–1162. doi:10.1111/j.1420-9101.2009.01732.x. PMID   19416416.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. Van Den Brandt, Marc Johan; Abdala, Fernando; Rubidge, Bruce Sidney (2019). "Cranial morphology and phylogenetic relationships of the Middle Permian pareiasaur Embrithosaurus schwarzi from the Karoo Basin of South Africa". Zoological Journal of the Linnean Society. doi:10.1093/zoolinnean/zlz064.
  6. Sues, Hans-Dieter; Reisz, Robert R. (1998-04-01). "Origins and early evolution of herbivory in tetrapods". Trends in Ecology & Evolution. 13 (4): 141–145. doi:10.1016/S0169-5347(97)01257-3. ISSN   0169-5347. PMID   21238234.
  7. Kriloff, A.; Germain, D.; Canoville, A.; Vincent, P.; Sache, M.; Laurin, M. (2008). "Evolution of bone microanatomy of the tetrapod tibia and its use in palaeobiological inference". Journal of Evolutionary Biology. 21 (3): 807–826. doi: 10.1111/j.1420-9101.2008.01512.x . PMID   18312321. S2CID   6102313.
  8. 1 2 Boitsova, Elizaveta A; Skutschas, Pavel P; Sennikov, Andrey G; Golubev, Valeriy K; Masuytin, Vladimir V; Masuytina, Olga A (2019-07-05). "Bone histology of two pareiasaurs from Russia (Deltavjatia rossica and Scutosaurus karpinskii) with implications for pareiasaurian palaeobiology". Biological Journal of the Linnean Society: blz094. doi:10.1093/biolinnean/blz094. ISSN   0024-4066.
  9. Gauthier, J.A.; Kluge, A.G.; Rowe, T. (1988). "The early evolution of the Amniota". In Benton, M.J. (ed.). The Phylogeny and Classification of the Tetrapods. Vol. 1. Oxford: Clarendon Press. pp. 103–155. ISBN   978-0198577058.
  10. Laurin, M.; Reisz, R.R. (1995). "A reevaluation of early amniote phylogeny". Zoological Journal of the Linnean Society. 113 (2): 165–223. doi:10.1111/j.1096-3642.1995.tb00932.x.
  11. LEE, M. S. Y. (1995). "Historical burden in systematics and the interrelationships of 'parareptiles'". Biological Reviews of the Cambridge Philosophical Society. 70 (3): 459–547. doi:10.1111/j.1469-185x.1995.tb01197.x. S2CID   85790423.
  12. Olroyd, Savannah L.; Sidor, Christian A. (August 2017). "A review of the Guadalupian (Middle Permian) global tetrapod fossil record". Earth-Science Reviews. 171: 583–597. Bibcode:2017ESRv..171..583O. doi: 10.1016/j.earscirev.2017.07.001 .
  13. Lee, M.S.Y. (1997). "Pareiasaur phylogeny and the origin of turtles". Zoological Journal of the Linnean Society. 120 (3): 197–280. doi: 10.1111/j.1096-3642.1997.tb01279.x .
  14. Jalil, N.-E.; Janvier, P. (2005). "Les pareiasaures (Amniota, Parareptilia) du Permien supérieur du Bassin d'Argana, Maroc". Geodiversitas. 27 (1): 35–132.
  15. Schoch, Rainer R.; Sues, Hans-Dieter (2015). "A Middle Triassic stem-turtle and the evolution of the turtle body plan". Nature. 523 (7562): 584–587. Bibcode:2015Natur.523..584S. doi:10.1038/nature14472. PMID   26106865. S2CID   205243837.
  16. Crawford, Nicholas G.; Parham, James F.; Sellas, Anna B.; Faircloth, Brant C.; Glenn, Travis C.; Papenfuss, Theodore J.; Henderson, James B.; Hansen, Madison H.; Simison, W. Brian (February 2015). "A phylogenomic analysis of turtles". Molecular Phylogenetics and Evolution. 83: 250–257. doi:10.1016/j.ympev.2014.10.021. PMID   25450099.
  17. Tsuji, L. A.; Sidor, C. A.; Steyer, J. - S. B.; Smith, R. M. H.; Tabor, N. J.; Ide, O. (2013). "The vertebrate fauna of the Upper Permian of Niger—VII. Cranial anatomy and relationships of Bunostegos akokanensis (Pareiasauria)". Journal of Vertebrate Paleontology. 33 (4): 747–763. Bibcode:2013JVPal..33..747T. doi:10.1080/02724634.2013.739537. S2CID   86097405.

Further reading