Intasuchus

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Intasuchus
Temporal range: Guadalupian, 272.5  Ma
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Intasuchus124DB.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Temnospondyli
Superfamily: Archegosauroidea (?)
Family: Intasuchidae
Konzhukova, 1956
Genus: Intasuchus
Konzhukova, 1956
Type species
Intasuchus silvicola
Konzhukova, 1956

Intasuchus is an extinct genus of temnospondyl amphibian from the Middle Permian of Russia. It is known from a single species, Intasuchus silvicola, which was named in 1956. Intasuchus belongs to the family Intasuchidae and is probably its sole member, although other taxa such as Syndyodosuchus and Cheliderpeton have been assigned to the family in the past. Intasuchus most likely belongs to the group Archegosauroidea, Permian relatives of the large, mostly Mesozoic temnospondyl clade Stereospondyli.

Contents

Description

Intasuchus has a long, flattened skull that narrows slightly toward the front. Prominent ridges run along the skull surface from the eye sockets to the nostril openings. The otic notch at the back of the skull is relatively narrow in comparison to other temnospondyls, although it extends as a groove along the sides of the skull table. Intasuchus has large teeth on the roof of its mouth, with a large row between two openings of the palate called choanae, tusks on the palatine bones, and small teeth extending along the ectopterygoid. [1]

Classification

The phylogenetic analysis of Schoch and Milner (2000) placed Intasuchus as a basal member of a group called Archegosauriformes. It was placed among archegosauroids, although Archegosauroidea was found to be a paraphyletic assemblage of taxa basal to Stereospondyli. Intasuchus silvicola was recovered as the sister taxon of Cheliderpeton latirostre (now known as Glanochthon latirostre ). Below is a cladogram from that analysis: [2] [3]

Archegosauriformes

Sclerocephalus haeuseri

Cheliderpeton vrayni

Cheliderpeton latirostre

Intasuchus silvicola

Archegosaurus dyscriton

Archegosaurus decheni

Collidosuchus tchudinovi

Platyoposaurus stuckenbergi

Australerpeton cosgriffi

Melosaurus uralensis

Konzhukovia vetusta

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<i>Mastodonsaurus</i> Extinct genus of amphibians

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<i>Rhinesuchus</i> Extinct genus of amphibians

Rhinesuchus is a large temnospondyl amphibian. Remains of the genus are known from the Permian of the South African Karoo Basin's Tapinocephalus and Cistecephalus assemblage zones, both belonging to the Beaufort Group. The skull of Rhinesuchus had a flat triangular shape with blunt snout similar to some of the other large amphibians, and had a palate filled with small sharp teeth, suggesting that it hunted fish. Also, the small eyes were on top of the head suggesting that it approached its prey from below.

<i>Eryosuchus</i> Extinct genus of amphibians

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<i>Cheliderpeton</i> Extinct genus of amphibians

Cheliderpeton is an extinct genus of temnospondyl amphibian. It lived during the Early Permian in what is now Europe. Fossils have been found from the Ruprechtice horizon of the Intrasudetic Basin of Bohemia in the Czech Republic, as well as the Saar-Nahe Basin of southwestern Germany. Cheliderpeton had a 16 cm skull, and reached about 65 cm in length.

<i>Dvinosaurus</i> Extinct genus of amphibians

Dvinosaurus is an extinct genus of amphibious temnospondyls localized to regions of western and central Russia during the middle and late Permian, approximately 265-254 million years ago. Its discovery was first noted in 1921 by Russian paleontologist Vladimir Prokhorovich Amalitskii in a posthumously published paper that documents the findings of a site in Russia's Arkhangelsk District. Its name is derived from the proximity of this site to the Northern Dvina River.

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<i>Konzhukovia</i> Genus of amphibians (fossil)

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<i>Australerpeton</i> Extinct genus of amphibians

Australerpeton is an extinct genus of stereospondylomorph temnospondyl currently believed to belong to the family Rhinesuchidae. When first named in 1998, the genus was placed within the new family Australerpetontidae. However, studies published a few years later questioned the systematics used in the original description and included the genus within Archegosauridae. A study by Dias & Schultz (2003) reassigned Australerpeton to the family Rhinesuchidae within the suborder Stereospondyli based on an earlier evaluation of the family. In this study, the close similarities between Australerpeton and archegosaurids were attributed to convergent evolution as a result of similar semi-aquatic lifestyles. A redescription of the skeleton of this genus was published by Eltink & Langer in 2014, and the skull was redescribed in a follow-up study published by Eltink et al. in 2016. These studies, as well as a 2017 study focusing on rhinesuchids in general, confirmed that Australerpeton was a rhinesuchid rather than an archegosaurid. Fossils of the genus have been found in the Rio do Rasto Formation of Brazil.

<span class="mw-page-title-main">Rhinesuchidae</span> Extinct family of amphibians

Rhinesuchidae is a family of tetrapods that lived primarily in the Permian period. They belonged to the broad group Temnospondyli, a successful and diverse collection of semiaquatic tetrapods which modern amphibians are probably descended from. Rhinesuchids can be differentiated from other temnospondyls by details of their skulls, most notably the interior structure of their otic notches at the back of the skull. They were among the earliest-diverging members of the Stereospondyli, a subgroup of temnospondyls with flat heads and aquatic habits. Although more advanced stereospondyls evolved to reach worldwide distribution in the Triassic period, rhinesuchids primarily lived in the high-latitude environments of Gondwana during the Guadalupian and Lopingian epochs of the Permian. The taxonomy of this family has been convoluted, with more than twenty species having been named in the past; a 2017 review recognized only eight of them to be valid. While several purported members of this group have been reported to have lived in the Triassic period, most are either dubious or do not belong to the group. However, at least one valid genus of rhinesuchid is known from the early Triassic, a small member known as Broomistega. The most recent formal definition of Rhinesuchidae, advocated by Mariscano et al. (2017) is that of a stem-based clade containing all taxa more closely related to Rhinesuchus whaitsi than to Lydekkerina huxleyi or Peltobatrachus pustulatus. A similar alternate definition is that Rhinesuchidae is a stem-based clade containing all taxa more closely related to Uranocentrodon senekalensis than to Lydekkerina huxleyi, Trematosaurus brauni, or Mastodonsaurus giganteus.

<span class="mw-page-title-main">Lydekkerinidae</span> Extinct family of amphibians

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<span class="mw-page-title-main">Stereospondylomorpha</span> Extinct clade of amphibians

Stereospondylomorpha is a clade of temnospondyls. It includes the superfamily Archegosauroidea and the more diverse group Stereospondyli. Stereospondylomorpha was first proposed by Yates and Warren (2000), who found Archegosauroidea and Stereospondyli to be sister taxa in their phylogenetic analysis. A similar clade is Archegosauriformes, named by Schoch and Milner (2000), which includes Stereospondyli and some Permian temnospondyls that are similar in appearance to stereospondyls, including the archegosauroids. However, according to Schoch and Milner's phylogeny, Archegosauroidea is a paraphyletic group of taxa that are successively basal to Stereospondyli, rather than a monophyletic sister taxon.

<span class="mw-page-title-main">Limnarchia</span> Extinct clade of amphibians

Limnarchia is a clade of temnospondyls. It includes the mostly Carboniferous-Permian age Dvinosauria and the mostly Permian-Triassic age Stereospondylomorpha. The clade was named in a 2000 phylogenetic analysis of stereospondyls and their relatives. Limnarchia means "lake rulers" in Greek, in reference to their aquatic lifestyles and long existence over a span of approximately 200 million years from the Late Carboniferous to the Early Cretaceous. In phylogenetic terms, Limnarchia is a stem-based taxon including all temnospondyls more closely related to Parotosuchus than to Eryops. It is the sister group of the clade Euskelia, which is all temnospondyls more closely related to Eryops than to Parotosuchus. Limnarchians represent an evolutionary radiation of temnospondyls into aquatic environments, while euskelians represent a radiation into terrestrial environments. While many euskelians were adapted to life on land with strong limbs and bony scutes, most limnarchians were better adapted for the water with poorly developed limbs and lateral line sensory systems in their skulls.

<i>Acroplous</i> Extinct genus of amphibians

Acroplous is an extinct genus of dvinosaurian Temnospondyli within the family Eobrachyopidae.

<i>Thoosuchus</i> Extinct genus of amphibians

Thoosuchus is an extinct genus of basal trematosauroid trematosaurian temnospondyl. Fossils have been found from Russia and date back to the Early Triassic. It is the type genus of the family Thoosuchidae, formerly called the subfamily Thoosuchinae and placed within Benthosuchidae. The benthosuchids were originally composed of the majority of basal trematosaurian forms regarded as the ancestors of the trematosaurids. Although the genus was first named in 1940, material from one species, E. yakovlevi, was originally tentatively referred to Trematosuchus in 1926.

Tersomius is an extinct genus of dissorophoid temnospondyl within the family Micropholidae. It is known from the early Permian of North America.

Perryella is an extinct genus of dvinosaurian(?) temnospondyl from the Permian of Oklahoma.

Parioxys is an extinct genus of temnospondyl amphibian from the Early Permian of Texas.

Palatinerpeton is an extinct genus of temnospondyl amphibian. Fossils have been found in the Lauterecken-Odernheim Formation of Germany.

References

  1. Shishkin, M.A.; Novikov, I.V.; Gubin, Y.M. (2003). "Permian and Triassic temnospondyls from Russia". In Benton, M.J.; Shishkin, M.A.; Unwin, D.M. (eds.). The Age of Dinosaurs in Russia and Mongolia. Cambridge: Cambridge University Press. pp. 35–59. ISBN   9780521545822.
  2. Schoch, R. R.; Milner, A. R. (2000). "Stereospondyli". In P. Wellnhofer (ed.). Handbuch der Paläoherpetologie. Vol. 3B. Munich: Verlag Dr. Friedrich Pfeil. p. 203.
  3. Stayton, C. T.; Ruta, M. (2006). "Geometric Morphometrics of the Skull Roof of Stereospondyls (Amphibia: Temnospondyli)". Palaeontology. 49 (2): 307. doi: 10.1111/j.1475-4983.2006.00523.x .