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The Permian is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years (Ma) ago, to the beginning of the Triassic Period 251.9 Ma ago. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia.
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids than they are to shelled nautiloids such as the living Nautilus species. The earliest ammonites appeared during the Devonian, and the last species either vanished in the Cretaceous–Paleogene extinction event, or shortly after, during the Danian epoch of the Paleocene.
In the geologic time scale, the Changhsingian or Changxingian is the latest age or uppermost stage of the Permian. It is also the upper or latest of two subdivisions of the Lopingian Epoch or Series. The Changhsingian lasted from 254.14 to 251.902 million years ago (Ma). It was preceded by the Wuchiapingian and followed by the Induan.
The Induan is the first age of the Early Triassic epoch in the geologic timescale, or the lowest stage of the Lower Triassic series in chronostratigraphy. It spans the time between 251.902 Ma and 251.2 Ma. The Induan is sometimes divided into the Griesbachian and the Dienerian subages or substages. The Induan is preceded by the Changhsingian and is followed by the Olenekian.
Araxoceras is an extinct genus of ceratitid ammonites that lived in the Late Permian marine environments of Iran, South China and Japan. The various species had distinctive, angular-cornered shells.
Endothiodon is an extinct genus of large dicynodont from the Late Permian. Like other dicynodonts, Endothiodon was an herbivore, but it lacked the two tusks that characterized most other dicynodonts. The anterior portion of the upper and lower jaw are curved upward, creating a distinct beak that is thought to have allowed them to be specialized grazers.
Wangwusaurus is extinct genus of probable therapsid that lived in the Late Permian in present-day China. Only species is known, Wangwusaurus tayuensis, described by the paleontologist Yang Zhongjian in 1979 from seventeen teeth found in the Jiyuan formation, of which at least seven are recognized as not belonging to those of therapsids.
Ingentidens is an extinct genus of chroniosuchid reptiliomorph from upper Permian mudstone deposits of Dashankou locality, Xidagou Formation of China. It was first named by Jin-Ling Li and Zheng-Wu Cheng in 1999, from a mandible. The type species is Ingentidens corridoricus. The generic name means “large” + “tooth” (dens), and the specific name referring to the region of Gansu, the Hexi Corridor where the type specimen was found.
Phratochronis is an extinct genus of chroniosuchid reptiliomorph from upper Permian mudstone deposits of Dashankou locality, Xidagou Formation of China. It was first named by Jin-Ling Li and Zheng-Wu Cheng in 1999, from a maxilla and premaxilla with almost complete dentition. The type species is Phratochronis qilianensis. The generic name means “brothers of a clan” + “late” in reference to its taxonomic position, and the specific name referring to the chain of mountains where the type specimen was found.
Macroolithus is an oogenus of dinosaur egg belonging to the oofamily Elongatoolithidae. The type oospecies, M. rugustus, was originally described under the now-defunct oogenus name Oolithes. Three other oospecies are known: M. yaotunensis, M. mutabilis, and M. lashuyuanensis. They are relatively large, elongated eggs with a two-layered eggshell. Their nests consist of large, concentric rings of paired eggs. There is evidence of blue-green pigmentation in its shell, which may have helped camouflage the nests.
Dromotectum is an extinct genus of bystrowianid reptiliomorph from the Late Permian of China and Early Triassic of Russia. Two species have been named: the type species D. spinosum and the species D. largum. D. spinosum, the first species to be named, comes from Lower Triassic deposits in the Samara Region of European Russia and is known from the holotype PIN 2424/23, which consists of armor scutes, and from PIN 2424/65, 4495/14 and 2252/397. It was found in the Staritskaya Formation of the Rybinskin Horizon and named by I.V. Novikov and M.A. Shishkin in 2000. The generic name means “corridor with hipped vault” + “roof” (tecton), and the specific name means “spinous”. A second species, D. largum, was named by Liu Jun, Xu Li, Jia Song-Hai, Pu Han-Yong, and Liu Xiao-Ling in 2014 from the Shangshihezi Formation near Jiyuan in Henan province, China on the basis of specimen IVPP V 4013.1, a large scute.
Kingoceras is a genus of ammonoids in the order Ceratitida and family Paraceltitidae which lived during the Late Permian from about 265 to about 254 million years ago. The shell is thinly lenticular, sutures are goniatitic and have only eight fully distinct lobes.
Doulingoceras is a genus of ammonoid within the ceratitid order, found in China, that lived during the Late Permian during the time span from about 260.5 to 254 million years ago. The genus is included in the family Paraceltitidae, which belongs to the superfamily Xenodiscaceae.
Syops is an extinct genus of dicynodont therapsid. The type species S. vanhoepeni was first named in 1938 as Dicynodon vanhoepeni. Fossils of the genus have been found in the Cistecephalus Assemblage Zone in the Usili Formation of the Ruhuhu Basin, Tanzania and Madumabisa Mudstone, Zambia. Its phylogenetic placement is somewhat uncertain, with multiple different studies finding it as either a basal geikiid, rhachiocephalid a dicynodontoid more derived than the most basal genera but less derived than Lystrosauridae, or a lystrosaurid.
Kunpania is an extinct genus of dicynodont therapsid from the Quanzijie Formation of Xinjiang, China. The type and only species is K. scopulusa, and it is known only by a single incomplete specimen including parts of the skull and forelimb. Since its initial description in 1978 by palaeontologist Ailing Sun, it has sometimes been considered to be another species of Dicynodon by other researchers, or potentially undiagnostic. However, a redescription in 2021 reaffirmed its distinctiveness, including a uniquely well developed muscle attachment on the humerus. Kunpania is perhaps the oldest known member of the derived dicynodont group Dicynodontoidea, potentially dating to the Middle Permian period during the Capitanian, and so may fill a knowledge gap in the history of dicynodont evolution.
Jiyuanitectum is an extinct genus of chroniosuchian tetrapod from the Late Permian Shangshihezi Formation of China. It is known from a single bony scute from Jiyuan in Henan province, ascribed to the type species Jiyuanitectum flatum in 2014. Plate-like scutes, which formed armor-like coverings on the backs of chroniosuchians, are the most commonly found chroniosuchian remains. They are also the most informative when it comes to distinguishing between species due to small variations in scute anatomy between different taxa. For example, a shallow groove along the midline of the scute is unique to Jiyuanitectum. The flatness of the scute is another unusual characteristic, giving it the species name flatum. Jiyuanitectum shares several features in common with the chroniosuchians Synesuchus and Bystrowiella, including the upper surface of the scute being covered in ridges that are mostly oriented perpendicular to the midline, and the absence of a bony projection on the front of the scute called the anteromedial articular processes, which is seen in other chroniosuchians. These features suggest that Jiyuanitectum belongs to the family Bystrowianidae. The narrowness of the scute suggests that it may be one of the most basal members of the group.
Baiera is a genus of prehistoric gymnosperms in the order Ginkgoales. It is one of the oldest fossil foliage types of Ginkgoales, and is related to the genera Ginkgo and Ginkgoites. Fossils of Baiera are found worldwide, and have been known from the Permian to the Cretaceous.
Counillonia is an extinct genus of dicynodont therapsid from the area of Luang Prabang in Laos, Southeast Asia that lived at around the time of the Permian-Triassic boundary and possibly dates to the earliest Early Triassic. Its type and only known species is C. superoculis. Counillonia was related to the Triassic dicynodonts such as Lystrosaurus and the Kannemeyeriiformes that survived the Permian mass extinction, but it was more closely related to the Permian genus Dicynodon than to either of these lineages. Counillonia may then possibly represent another line of dicynodonts that survived the Permian mass extinction into the Triassic period, depending on its age. The discovery of Counillonia in Laos and its unexpected evolutionary relationships hint at the less well understood geographies of dicynodont diversity across the Permo-Triassic boundary outside of well explored regions like the Karoo Basin in South Africa.
Kembawacela is an extinct genus of cistecephalid dicynodont from the Late Permian Madumabisa Mudstone Formation of Zambia. It contains the type and only species, Kembawacela kitchingi. Like other cistecephalids, Kembawacela was specialised for a fossorial, burrowing lifestyle similar to modern day moles. It is unique amongst cistecephalids for the presence of a pair of tusks in the upper jaw, characteristic of many other dicynodonts but lost in other cistecephalids. It is likely that Kembawacela was a locally endemic species of cistecephalid in the Luangwa Basin of Zambia.
Taoheodon is an extinct genus of dicynodont therapsid from the Sunjiagou Formation in the Shanxi province of China, dated to the Wuchiapingian age of the Late Permian. Its type and only known species is T. baizhijuni. Taoheodon was a close relative of the well known Dicynodon, and may represent a biogeographical link between the South African Dicynodon and similar dicynodonts found in Laos.
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