Horezmia | |
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Genus: | Horezmia |
Horezmia is an extinct Mesozoic genus of prehistoric salamanders. [1] [2] The fossils have been found in Russia. It is comparable to modern advanced salamanders, though its phylogenetic placement within Salamandroidea is uncertain.
The Cryptobranchidae are a family of fully aquatic salamanders commonly known as the giant salamanders. They include the largest living amphibians. The family is native to China, Japan, and the eastern United States. They constitute one of two living families—the other being the Asiatic salamanders belonging to the family Hynobiidae—within the Cryptobranchoidea, one of two main divisions of living salamanders.
The Caudata are a group of amphibians containing the extant salamanders and all extinct species of amphibians more closely related to salamanders than to frogs. They are typically characterized by a superficially lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults.
The Albanerpetontidae are an extinct family of small amphibians, native to the Northern Hemisphere during the Mesozoic and Cenozoic. The only members of the order Allocaudata, they are thought to be allied with living amphibians belonging to Lissamphibia. Despite a superficially salamander-like bodyform, their anatomy is strongly divergent from modern amphibians in numerous aspects. The fossil record of albanerpetontids spans over 160 million years from the Middle Jurassic to the beginning of the Pleistocene, about 2.13–2 million years ago.
Chunerpeton tianyiensis is an extinct species of salamander from the Late Jurassic Daohugou Beds in Ningcheng County, Nei Mongol, China. It is the only species classified under the genus Chunerpeton, which means "early creeping animal". It was a small animal measuring 18 cm in length. It was neotenic, with the retention of external gills into adulthood. In the original description it was placed in Cryptobranchidae, which contains modern giant salamanders. A redescription published in 2020 found it to be a stem-group caudatan outside the crown group of modern salamanders. A 2021 study found it to be a member of Cryptobranchoidea outside of Cryptobranchidae. In 2022 a more extensive analysis, with greater character and taxon sampling, recovered Chunerpeton tianyiense as a stem-group caudatan, outside the crown group of modern salamanders, and associated with Beiyanerpeton jianpingensis and Qinglongtriton gangouensis.
Eoscapherpeton is an extinct genus of giant salamander, known from the Late Cretaceous of Central Asia. Fossils have been found in the Cenomanian aged Khodzhakul Formation and Dzharakuduk Formation, Turonian aged Bissekty Formation and the Coniacian-Santonian aged Aitym Formation of Uzbekistan, the Santonian aged Yalovach Formation of Tajikistan, and the Santonian-lower Campanian aged Bostobe Formation and Campanian aged Darbasa Formation of Kazakhstan.
Hylaeobatrachus is an extinct genus of prehistoric salamander, known from the Early Cretaceous of Europe. The type species H. croyii is known from the Sainte-Barbe Clays Formation at the Iguanodon locality of Belgium, and was described by Louis Dollo. An unnamed Hylaeobatrachus-like taxon has also been reported from Las Hoyas, Spain. Both localities are of Barremian age. Hylaeobatrachus belongs to the crown group of modern salamanders, though its exact relationship with modern salamander groups is uncertain. It was neotenic, llike some modern salamanders.
Liaoxitriton is an extinct genus of prehistoric cryptobranchoid salamanders from the Early Cretaceous of China. It contains one species, L. zhongjiani, from the Aptian aged Yixian Formation. A second species, L. daohugouensis from the Middle/Late Jurassic Daohugou Beds, was moved to the genus Neimengtriton in 2021 after a number of studies noted morphological differences between the two genera.
Kokartus is an extinct genus of prehistoric stem-group salamander (Caudata) from the Middle Jurassic Balabansai Formation of Kyrgyzstan.
Marmorerpeton is an extinct genus of prehistoric stem group-salamanders that lived in Britain during the Bathonian stage of the Middle Jurassic. They are among the oldest known salamanders. Two species were named when the genus was first described by Susan E. Evans et al. in 1988, M. freemani, and M. kermacki, from fragmentary remains found via screenwashing in the Forest Marble Formation of England. Due to the size of their osteocytic lacunae suggesting a large genome size and some morphological characters, like the presence of calcified cartilage in the medulla of its humerus, it was assumed that Marmorerpeton was neotenic. New more complete remains of a new species M. wakei were described in 2022 from the Kilmaluag Formation of the Isle of Skye, Scotland. These conclusively demonstrated that Marmorerpeton was neotenic, and was a member of the family Karauridae, with the other two members of the family, Karaurus and Kokartus being known from the Middle-Late Jurassic of Central Asia. The teeth appear to have been weakly pedicellate.
Valdotriton is a genus of extinct prehistoric salamanders. Its only known species is Valdotriton gracilis. V. gracilis lived during the Late Barremian in what is now Spain. It was found in the Las Hoyas locality. It represents one of the oldest known members of Salamandroidea.
Plagiobatrachus is an extinct genus of plagiosaurid temnospondyl. It is known from the Rewan Formation, an Early Triassic formation in Australia.
Pangerpeton is an extinct genus of salamanders. Its monotypic species is Pangerpeton sinensis.
The Balabansai Formation is a geological formation in Kazakhstan, Kyrgyzstan and Uzbekistan whose strata date back to the Bathonian and Callovian stages of the Middle Jurassic. Dinosaur remains are among the fossils that have been recovered from the formation. The lithology primarily consists of variegated sandstones, siltstones, claystones, and rare gravels and marls. Many taxa have been found in the formation, including amphibians and mammals
The Itat Formation is a geologic formation in western Siberia. It was deposited in the Bajocian to Bathonian ages of the Middle Jurassic. Dinosaur remains are among the fossils that have been recovered from the formation, including the proceratosaurid Kileskus, as well as fish, amphibians, mammals and many other vertebrates. The formation is noted for bearing significant coal reserves, with large open pit coal mines extracting lignite from the unit currently in operation.
Nesovtriton is an extinct genus of cryptobranchoid salamander known from the Late Cretaceous of Bissekty Formation, in Uzbekistan. It was first named by Pavel P. Skutschas in 2009 and the type species is Nesovtriton mynbulakensis.
Seminobatrachus is an extinct genus of neotenic salamander from late Paleocene to early Eocene deposits of Cherkassy Region, central Ukraine. It is known from 14 skeletons from a drill hole near Boltyshka village. It was first named by Pavel P. Skutschas and Yuri M. Gubin in 2011 and the type species is Seminobatrachus boltyschkensis.
The Karauridae are a family of stem-group salamanders (Caudata) that are known from the Middle Jurassic to Late Jurassic in Central Asia and Western Europe. The family includes three members: Karaurus from the Middle-Late Jurassic Karabastau Formation of Kazakhstan, Kokartus from the Middle Jurassic Balabansai Formation of Kyrgyzstan, and Marmorerpeton from the Middle Jurassic Forest Marble Formation of England and Kilmaluag Formation of Scotland. The members are some of the oldest known salamanders. The family is united by several morphological characters, including sculptured skull roof bones. Like some modern salamanders, karaurids were neotenic. Members of the family likely fed via suction feeding on small fish and invertebrates. The Early Cretaceous Siberian Kulgeriherpeton has been suggested to be a karaurid by some authors.
The Moskvoretskaya Formation is a Middle Jurassic geologic formation in the European part of Russia. It consists of continental claystones, siltstones and sandstones deposited in karstified segments of underlying Middle Carboniferous limestone, that would have formed underground aquifers.
The Batylykh Formation is a geological formation in Yakutia, Russia. It is of an uncertain Early Cretaceous age, probably dating between the Berriasian and the Barremian. It is the oldest unit of the 1,500 metres (4,900 ft) thick Sangar Series within the Vilyuy syneclise. The mudstones, sandstones and shales of the formation were deposited in a fluvial to lacustrine environment.
Triassurus is an extinct genus of amphibian, and the oldest member of Caudata. It is known from the Middle to Upper Triassic (Ladinian-Carnian) aged Madygen Formation in Kyrgyzstan. The type species is T. sixtelae.