Dianmeisaurus Temporal range: Middle Triassic, | |
---|---|
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Superorder: | † Sauropterygia |
Order: | † Nothosauroidea |
Suborder: | † Pachypleurosauria |
Genus: | † Dianmeisaurus Shang & Li, 2015 |
Type species | |
†Dianmeisaurus gracilis Shang & Li, 2015 |
Dianmeisaurus is an extinct genus of pachypleurosaur from the Middle Triassic Guanling Formation in China. The type species is D. gracilis. [1]
The Jurassic is a geologic period and stratigraphic system that spanned from the end of the Triassic Period 201.3 million years ago (Mya) to the beginning of the Cretaceous Period, approximately 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified.
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 251.902 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.
In the geologic timescale, the Olenekian is an age in the Early Triassic epoch; in chronostratigraphy, it is a stage in the Lower Triassic series. It spans the time between 251.2 Ma and 247.2 Ma. The Olenekian is sometimes divided into the Smithian and the Spathian subages or substages. The Olenekian follows the Induan and is followed by the Anisian.
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.
Saurichthys is an extinct genus of predatory ray-finned fish from the Triassic period. It is the name giving genus of the family Saurichthyidae. This family also includes the Permian Eosaurichthys (China) and the Jurassic Saurorhynchus from Europe and North America.
The Stereospondyli are a group of extinct temnospondyl amphibians that existed primarily during the Mesozoic period. They are known from all seven continents and were common components of many Triassic ecosystems, likely filling a similar ecological niche to modern crocodilians prior to the diversification of pseudosuchian archosaurs.
Thalattosauria is an extinct order of prehistoric marine reptiles that lived in the middle to late Triassic period. Thalattosaurs were diverse in size and shape, and are divided into two superfamilies: Askeptosauroidea and Thalattosauroidea. Askeptosauroids were endemic to the Tethys Ocean, their fossils have been found in Europe and China, and they were likely semiaquatic fish eaters with straight snouts and decent terrestrial abilities. Thalattosauroids were more specialized for aquatic life and most had unusual downturned snouts and crushing dentition. Thalattosauroids lived along the coasts of both Panthalassa and the Tethys Ocean, and were most diverse in China and western North America. The largest species of thalattosaurs grew to over 4 meters (13 feet) in length, including a long, flattened tail utilized in underwater propulsion. Although thalattosaurs bore a superficial resemblance to lizards, their exact relationships are unresolved. They are widely accepted as diapsids, but experts have variously placed them on the reptile family tree among Lepidosauromorpha, Archosauromorpha, ichthyosaurs, and/or other marine reptiles.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2000.
Pteronisculus is an extinct genus of prehistoric bony fish that lived during the Early Triassic and Middle Triassic epochs of the Triassic period. The preoccupied genus name "Glaucolepis" Stensiö, 1921 is a synonym of Pteronisculus White, 1933.
Luganoia is an extinct genus of prehistoric bony fish that lived during the early Ladinian stage of the Middle Triassic epoch.
Ptychoceratodus is an extinct genus of lungfish living from Early Triassic to Middle Jurassic. It was established by Otto Jaekel for one species, transferred from Ceratodus genus. Type species is P. serratus from the Middle Triassic of Switzerland and Germany. Ptychoceratodus had two pairs of massive dental plates, bearing 4-6 acute ridges. Its skull roof was composed from massive, plate-like bones. In the central part of skull roof was localized an unossified fenestra. Most of the Ptychoceratodus findings are isolated dental plates, some associated with jaws. Other parts of skull or postcranial skeleton are relatively rarely found as fossils. The anatomy of skull is the best recognized in P. serratus, whereas less complete cranial material is available also for P. concinuus, P. phillipsi, and P. rectangulus. Although Ptychoceratodus is known exclusively from the Triassic and Jurassic, there were also Cretaceous specimens referred to this genus. However, they are more often regarded as representants of Metaceratodus. Ptychoceratodus is the only member of the family Ptychoceratodontidae. The first named species is P. phillipsi by Louis Agassiz in 1837 as a species of Ceratodus and later moved to Ptychoceratodus genus. Occurrences of Ptychoceratodus come mainly from Europe. However, occurrences from other continents suggest it was dispersed globally during the Triassic. After 2010, the new fossil material behind the Europe was reported from South America, India, and Greenland
The Ommatidae are a family of beetles in the suborder Archostemata. The Ommatidae are considered the extant beetle family that has most ancestral characteristics. There are only seven extant species, confined to Australia and South America. However, the geographical distribution was much wider during the Mesozoic spanning across Eurasia and Australia, suggesting that they were widespread on Pangea. So far, 28 extinct genera containing over 100 species of these beetles have been described. Three extant genera have been assigned to this family: Omma,Tetraphalerus and Beutelius. The family is considered to be a subfamily of Cupedidae by some authors, but have been found to be more closely related to Micromalthidae in molecular phylogenies. A close relationship with Micromalthidae is supported by several morphological characters, including those of the mandibles and male genitalia. Due to their rarity, their ecology is obscure, it is likely that their larvae feed on deadwood.
Saurichthyiformes is an extinct order of ray-finned fish which existed in Asia, Africa, Australia, Europe and North America, during the late Permian to early Middle Jurassic. Saurichthyiiformes comprise two families, Saurichthyidae and Yelangichthyidae. Whereas Yelangichthyidae is monotypic, Saurichthyidae includes at least two genera, Saurorhynchus and the very speciose Saurichthys. Additionally, the subgenera Costasaurichthys, Eosaurichthys, Lepidosaurichthys, and Sinosaurichthys are frequently used to group species. Saurichthyiforms were highly successful predators, and with Yelangichthys possibly even included durophagous forms. Species are known from both marine end freshwater deposits. They had their highest diversity during the Early and Middle Triassic.
Anshunsaurus is a genus of thalattosaurs within the family Askeptosauridae. Fossils have been found from Middle Triassic deposits in Guizhou, China. Three species are known: the type species A. huangguoshuensis, the slightly older species A. wushaensis, and the species A. huangnihensis.
Pistosauroidea is a group of marine reptiles within the superorder Sauropterygia that first appeared in the latter part of the Early Triassic and were the ancestors of plesiosaurs. Pistosauroids are rare in Triassic marine assemblages, and are represented by only a few fossils from central Europe, the United States, and China. Recent phylogenetic analyses consider the Triassic pistosauroids to be a paraphyletic grouping, meaning that they do not form a true clade. Plesiosauria is now placed within Pistosauroidea, while the traditional pistosauroids are successively more basal, or primitive, sauropterygians.
CNKI is a key national research and information publishing institution in China, led by Tsinghua University, and supported by PRC Ministry of Education, PRC Ministry of Science, Propaganda Department of the Chinese Communist Party and PRC General Administration of Press and Publication (GAPP). This project was launched in 1996 by Tsinghua University and Tsinghua Tongfang Company. Its first database was China Academic Journals Full-text Database, which rapidly became popular in China, especially in academic libraries. In 1999, CNKI started to develop online databases. To date, CNKI has built a comprehensive China Integrated Knowledge Resources System, including journals, doctoral dissertations, masters' theses, proceedings, newspapers, yearbooks, statistical yearbooks, ebooks, patents and standards. 10 services centers have been established, in Beijing, North America, Japan, North Korea, Taiwan and Hong Kong, and it is widely used by universities, research institutes, governments, think tanks, companies, hospitals and public libraries around the world. It also contains e-books for student usage.
Yang Shouren is a professor in the School of Earth and Space Sciences in Peking University.
Ginglymodi is a clade of ray-finned fish containing modern-day gars (Lepisosteidae) and their extinct relatives, including the family Lepidotidae and the orders Semionotiformes and Kyphosichthyiformes, and various other extinct taxa. Ginglymodi is one of the two major subgroups of the infraclass Holostei, the other one being Halecomorphi, which contains the bowfin and its fossil relatives.
Redfieldiiformes is an extinct order of ray-finned fish (actinopterygians) which lived from the Middle Triassic to Early Jurassic. Redfieldiiforms were fairly typical Triassic fish in overall anatomy. They had a fusiform body shape with thick, ganoine-covered scales. The dorsal and anal fins were large, positioned opposite from each other, and shifted back, close to the tail. The caudal fin was hemiheterocercal, with the vertebral column and body scales extending into an upper lobe which was equal in size and shape to the lower lobe. They also had several characteristic skeletal traits, such as a hatchet-shaped preopercle, a series of fulcra fringing the fins, a reduced number of branchiostegal rays, and a snout ornamented with tubercles.