Deltasaurus

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Deltasaurus
Temporal range: Late Triassic
Deltasaurus kimberleyensis.jpg
Restoration of Deltasaurus kimberleyensis
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Temnospondyli
Suborder: Stereospondyli
Family: Rhytidosteidae
Subfamily: Derwentiinae
Genus: Deltasaurus
Cosgriff, 1965 [1]
Type species
Deltasaurus kimberleyensis
Cosgriff, 1965
Other species
  • D. pustulatus
    Cosgriff, 1965

Deltasaurus is an extinct genus of Carnian temnospondyl amphibian of the family Rhytidosteidae.

Contents

Taxonomy

The genus was erected in 1965 by John W. Cosgriff, when describing two new species discovered northwest Australia. The author recognised an affinity with other genera allied to the family Rhytidosteidae that had been uncovered in Africa, and proposed their arrangement to a new superfamily Rhytidosteoidea.

D. kimberleyensis fossil Deltasaurus kimberleyensis 5.jpg
D. kimberleyensis fossil

It is the most common animal fossil of the Blina Shale, a fossil deposit at the eastern end of the Erskine Range in the Kimberley region of Western Australia. A specimen has also been collected from the Knocklofty Sandstone deposit in Tasmania. [2]

The genus places two fossil taxa, Deltasaurus kimberleyensis , the type species which grew to around 90 centimetres in length, and Deltasaurus pustulatus , also described by Cosgriff in 1965. [2] The genus has been variously placed in subsequent arrangements, at one time as a familia Derwentiidae that separated the Australian taxa from Indobrachyops found on the Indian subcontinent. A revision of the Rhytidosteidae (Stereospondyli: Trematosauria) published in 2011 applied phylogenetic methodologies to reassess the relationships of the genera and submerged the Derwentiidae as a new subfamily of Rhytidosteidae that included the genus Indobrachyops as an eastern Gondwanan grouping of Australian and Indian rhytidosteids. [3]

Distribution

A stereospondyl genus unearthed at sites located in Western Australia and Tasmania in shale deposits dated from the upper Permian to lower Triassic. [3]

Description

A temnospondyl amphibian of the family Rhytidosteidae. It had four limbs and a tail, and numerous tiny teeth. It is thought to have been a predator of fish. [2] Deltasaurus are distinguished from other Australia species of Rhytidosteidae by the straight side of the skull, rather than parabolic outline of Rewana quadricuneata , Arcadia myriadens and Derwentia warreni . [4]

Related Research Articles

<span class="mw-page-title-main">Temnospondyli</span> Ancestors of modern amphibians adapted to life on land

Temnospondyli or temnospondyls is a diverse ancient order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian and Triassic periods, with fossils being found on every continent. A few species continued into the Jurassic and Early Cretaceous periods, but all had gone extinct by the Late Cretaceous. During about 210 million years of evolutionary history, they adapted to a wide range of habitats, including freshwater, terrestrial, and even coastal marine environments. Their life history is well understood, with fossils known from the larval stage, metamorphosis and maturity. Most temnospondyls were semiaquatic, although some were almost fully terrestrial, returning to the water only to breed. These temnospondyls were some of the first vertebrates fully adapted to life on land. Although temnospondyls are amphibians, many had characteristics such as scales and armour-like bony plates that distinguish them from the modern soft-bodied lissamphibians.

Deltasaurus kimberleyensis was a temnospondyl amphibian of the family Rhytidosteidae that existed during the Carnian stage of the Triassic. The fossilised remains were discovered in the Blina Shale formation in the Kimberley region of northwest Australia in 1965.

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

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.

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

Laidleria is an extinct genus of temnospondyl that likely lived between the Early to Middle Triassic, though its exact stratigraphic range is less certain. Laidleria has been found in the Karoo Basin in South Africa, in Cynognathus Zone A or B. The genus is represented by only one species, L. gracilis, though the family Laidleriidae does include other genera, such as Uruyiella, sister taxon to Laidleria, which was discovered and classified in 2007. 

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

Konzhukovia is an amphibian genus that belongs to an extinct family Konzhukoviidae of temnospondyls, the largest clade of basal tetrapods including about 198 genera, 292 species, and more than half of which were alive during the early Mesozoic period. The animal was a predator that lived about 260 million years ago, and could get up to about three meters in length. Specifically, Konzukovia lived during the Permian, between 252 and 270 million years ago according to the type of rock the fossil was found in. There are three species within this genus, K. vetusta, K. tarda, and K. sangabrielensis, the first two originating from Russia while the latest originating from Southern Brazil. The discovery of this specimen in Southern Brazil provided more evidence to support the idea that during this animals existence, there was a “biological corridor” because of the supercontinent Pangea, allowing these species to be found so far apart from each other. Konzhukovia belongs to the family Archegosauridae, a family consisted of large temnospondyls that most likely compare to modern day crocodiles. Since the discovery of the latest species, K. sangabrielensis, Pacheco proposes that there must be the creation of a new family, Konzhokoviidae, a monophyletic group in a sister-group relationship with Stereospondlyi in order to accommodate the three species. Konzhukovia skulls usually exhibit typical rhinesuchid features including an overall parabolic shape, small orbits located more posteriorly, and the pterygoids do not reach the vomer. These animals were long-snouted amphibians that had clear adaptations made for fish catching, as well as exemplifying aquatic features.

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

Rhytidosteidae is a family of Temnospondyli that lived in the Permian and Triassic.

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

Lydekkerinidae is a family of stereospondyl temnospondyls that lived in the Early Triassic period. During this time period, lydekkerinids were widely distributed, with putative remains reported from Russia, Greenland, India, South Africa, Madagascar, Australia, and Antarctica. In contrast to most other stereospondyls, lydekkerinids were relatively small-bodied. The type genus is Lydekkerina, the namesake of the family and the best-known lydekkerinid.

Rhytidosteoidea is a superfamily of Temnospondyli, early amphibian species that existed during the Carboniferous, Permian, and Triassic periods. The taxon was established in 1965 to accommodate two new species of Deltasaurus, the author recognising an alliance with previously described genera.

Deltasaurus pustulatus is an amphibian fossil species of the family Rhytidosteidae. The temnospondyl hunted invertebrates and fish during the late stage Triassic epoch, and somewhat resembles the only other species of the eastern Gondwanan genus Deltasaurus. The only known evidence of the species was discovered in a drill core in Southwest Australia, near Geraldton, a seemingly improbable event that produced the only known example of Triassic vertebrate fauna in the ecologically exceptional region's Kockatea Formation.

Almasaurus is an extinct genus of trematosaurian temnospondyl within the family Latiscopidae. It is known from several skulls and some postcranial material found from the Argana Formation in Morocco, which dates back to the Late Triassic.

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

Bothriceps is an extinct genus of stereospondyl temnospondyl. It is a member of the infraorder Trematosauria and is the most basal brachyopomorph known. It is one of the only brachyopomorph that lies outside the superfamily Brachyopoidea, which includes the families Brachyopidae and Chigutisauridae. It shares several similarities to Keratobrachyops, another basal brachyopomorph, and may be closely related to or even synonymous with it.

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

Indobrachyops is an extinct genus of temnospondyl amphibian from the Early Triassic of India. It is known from a nearly complete fossil skull that was first described by paleontologists Friedrich von Huene and M. R. Sahni in 1958 from the Panchet Formation in Raniganj Coalfield. Indobrachyops belongs to a group of mostly semi-aquatic temnospondyls called Stereospondyli, but its exact placement within the group has been uncertain since its first description.

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

Lapillopsis is an extinct genus of stereospondyl temnospondyl within the family Lapillopsidae. Fossils belonging to the genus have been found in the Arcadia Formation of Queensland, Australia.

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

Rhineceps is an extinct genus of temnospondyl amphibian in the family Rhinesuchidae. Rhineceps was found in Northern Malawi in Southern Africa known only from its type species R. nyasaensis. Rhineceps was a late Permian semi-aquatic carnivore that lived in streams, rivers, lakes or lagoons. Rhineceps is an early divergent Stereopondyl within the family Rhinesuchidae, which only existed in the late Permian (Lopingian) and failed to survive the Permian-Triassic extinction unlike other stereospondyl families.

<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.

Pneumatostega is an extinct genus of rhytidosteid temnospondyl from the early Triassic period of Cape Province of South Africa. It is known from the holotype BPI F981, a dorsal mould of a skull roof and from the referred specimen SAM 11188, partial skull fragments and postcranial remains recovered from the Lystrosaurus Assemblage Zone in the Beaufort Group near Middelburg. This genus was named by J. W. Cosgriff and J. M. Zawiskie in 1979, and the type species is Pneumatostega potamia.

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

Trucheosaurus is an extinct genus of rhytidosteid temnospondyl from the Late Permian Glen Davis Formation of the Sydney Basin, New South Wales, Australia. It is known from the holotype materials MMF 12697a, a partially complete skull, AMF 50977, an articulated postcranial skeleton and BMNHR 3728, the counterpart of both skull and postcranial skeleton, recovered from the Glen Davis Formation. This genus was named by Watson in 1956, and the type species is Trucheosaurus major.

<span class="mw-page-title-main">Derwentiinae</span> Extinct subfamily of amphibians

Derwentiinae is a subfamily of rhytidosteid temnospondyls from the Permian and Triassic periods of Australia and India. It includes the genera Arcadia, Deltasaurus, Derwentia, Indobrachyops, and Rewana. Derwentiinae was named in a 2011 study that analyzed the phylogenetic relationships of rhytidosteids. It was a replacement name for the family Derwentiidae, which was named in 2000.

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

Rhytidosteus is an extinct genus of temnospondyl amphibian from the Early Triassic of South Africa. In 2019, the remains were also discovered in the Astrakhan region, Russia.

Latiscopus disjunctus is a small Late Triassic temnospondyl collected in 1940 by a Works Projects Administration crew working near Otis Chalk, Texas that was described by John Wilson in 1948.

References

  1. Cosgriff, J.W. (1965). "A new genus of Temnospondyli from the Triassic of-Western Australia". Journal of the Royal Society of Western Australia. 48: 65–90.
  2. 1 2 3 Warren, Anne (1987). "An Ancient Amphibian from Western Australia". In Hand, Suzanne and Michael Archer (ed.). The Antipodean Ark. Angus & Robertson. ISBN   0-207-15664-6.
  3. 1 2 Dias-da-Silva, S.; Marsicano, C. (1 June 2011). "Phylogenetic reappraisal of Rhytidosteidae (Stereospondyli: Trematosauria), temnospondyl amphibians from the Permian and Triassic". Journal of Systematic Palaeontology. 9 (2): 305–325. doi:10.1080/14772019.2010.492664. hdl: 11336/68471 . ISSN   1477-2019.
  4. Rozefelds, A.C.; Warren, A. (September 2011). "Lepidostrobus muelleri Johnston is a skull fragment of a temnospondyl amphibian". Alcheringa: An Australasian Journal of Palaeontology. 35 (3): 459–462. doi:10.1080/03115518.2011.527163.