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Parvosaurus
''Parvosaurus'' is an extinct species of rhynchocephalian reptile known from the Late Triassic of Germany. Discovery The specimen was discovered in the rock surrounding a specimen of ''Plateosaurus'' that had been collected from a brick pit located in Saxony-Anhalt between Halberstadt and Quedlinburg on the Bundesstraße 79 highway in sediments belonging to the Late Triassic (Norian) Arnstadt Formation by Werner Janensch in 1928. The specimen was not discovered until the block was CT scanned as part of the redescription of the small reptile ''Elachistosuchus'' in 2015. Description The species is only known from a skull and partial lower jaws. The skull has been compressed during fossilization. The specimen is thought to be a juvenile, as it has relatively large eyes and is small in size, with the skull only being around in length, comparable to that of ''Diphydontosaurus''. The dentition is very similar to that of ''Diphydontosaurus.'' Taxonomy ''Parvosaurus'' was placed as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arnstadt Formation
The Trossingen Formation, formerly the Knollenmergel (also known as the Arnstadt Formation), is a geological formation in Germany and Switzerland. It dates back to the late Norian-Rhaetian. It belongs to the Keuper Group of the Germanic Triassic. The ''Trossingen Formation'' is underlain by the Löwenstein Formation and erosively overlain by the Exter Formation, in part also directly by the Black Jurassic. Definition The horizontal boundary of the ''Trossingen Formation'' is a diachronous facies boundary and is characterized by the exposure of the sandstones of the Löwenstein Formation. The hanging wall boundary is also sharply defined facially and characterized by the erosive overburden with terrestrial sediments of various locally widespread strata of the Exter Formation (Malschenberg Clay or Sandstone, Contorta Clay, Tübingen Sandstone) or, in the case of the more extensive Upper Keuper Hiatus, directly with the dark marine mudstones of the Hettangian onwards Black J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhynchocephalia
Rhynchocephalia (; ) is an order of lizard-like reptiles that includes only one living species, the tuatara (''Sphenodon punctatus'') of New Zealand. Despite its current lack of diversity, during the Mesozoic rhynchocephalians were a speciose group with high morphological and ecological diversity. The oldest record of the group is dated to the Middle Triassic around 238 to 240 million years ago, and they had achieved global distribution by the Early Jurassic. Most rhynchocephalians belong to the group Sphenodontia ('wedge-teeth'). Their closest living relatives are lizards and snakes in the order Squamata, with the two orders being grouped together in the superorder Lepidosauria. Rhynchocephalians are distinguished from squamates by a number of traits, including the retention of rib-like gastralia bones in the belly, as well as most rhynchocephalians having acrodont teeth that are fused to the crests of the jaws (the latter also found among a small number of modern lizard grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gracilisuchid
Gracilisuchidae is an extinct family of suchian archosaurs known from the early Middle Triassic to the early Late Triassic (Anisian – early Carnian) of China, Argentina, and Brazil. Distribution Currently, the oldest known gracilisuchid is '' Turfanosuchus dabanensis'' from the Anisian stage of Xinjiang, China. Two gracilisuchids are known from the Ladinian or early Carnian stage, '' Gracilisuchus stipanicicorum'' and '' Yonghesuchus sangbiensis'', from La Rioja Province of Argentina, and Shanxi, respectively. These species were considered enigmatic prior to the recognition of the family in 2014, suggesting a rapid phylogenetic diversification of archosaurs by the Middle Triassic. This radiation is a part of the broader recovery of terrestrial ecosystems after the Permian–Triassic extinction event. Gracilisuchids are known from approximately similar northern and southern mid-palaeolatitudes, demonstrating a wide distribution of early archosaurs over much or all of Pangaea b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphydontosaurus
''Diphydontosaurus'' is an extinct genus of small Rhynchocephalia, rhynchocephalian reptile from the Late Triassic of Europe. It is the most primitive known member of Sphenodontia. Description ''Diphydontosaurus'' was one of the smallest sphenodontia, sphenodontians, measuring up to long. It had long, sharp claws to help it catch its prey. The skull, which was around long, had large Orbit (anatomy), orbits (eye sockets), as well as a combination of 17 regularly replaced conical pleurodont teeth on the front of the jaws and 11 larger permanent acrodont teeth in the posterior jaws. It was likely an insectivore which used its acrodont posterior teeth to dismember prey. Classification ''Diphydontosaurus avonis'' is known from abundant remains covering most of the skeleton found in fissure fill deposits in Southwest Britain. A skeleton of a juvenile sphenodontian tentatively referred to ''Diphydontosaurus'' was reported in 1996 from the Norian of Lombardy in Italy.Renesto, S., 1995 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Prehistoric Reptile Genera
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norian Genera
The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227.3 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic definitions The Norian was named after the Noric Alps in Austria. The stage was introduced into scientific literature by Austrian geologist Edmund Mojsisovics von Mojsvar in 1869. The Norian Stage begins at the base of the ammonite biozones of '' Klamathites macrolobatus'' and '' Stikinoceras kerri'', and at the base of the conodont biozones of '' Metapolygnathus communisti'' and '' Metapolygnathus primitius''. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Norian (the base of the Rhaetian) is at the first appearance of ammonite species '' Cochloceras amoenum''. The base of the Rheatian is also close to the first appearance of conodont species '' Misikella spp.'' and '' Epigondolella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clevosaurus
''Clevosaurus'' (meaning "Gloucester lizard") is an extinct genus of rhynchocephalian reptile from the Late Triassic and the Early Jurassic periods. Species of ''Clevosaurus'' were widespread across Pangaea, and have been found on all continents except Australia and Antarctica. Five species of ''Clevosaurus'' have been found in ancient fissure fill deposits in south-west England and Wales, alongside other sphenodontians, early mammals and dinosaurs. In regards to its Pangaean distribution, ''C. hadroprodon'' is the oldest record of a sphenodontian from Gondwana, though its affinity to ''Clevosaurus'' has been questioned. History of discovery The first species of ''Clevosaurus'' to be described was ''C. hudsoni'', which was described by William Elgin Swinton in 1939 from a fissure fill deposit in Cromhall Quarry ( Magnesian Conglomerate Formation) in the county of Gloucestershire, England, with the name of the county lending its name to the genus. Another notable specimen was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gephyrosaurus
Gephyrosaurus is an extinct genus of lepidosaurian reptile known from the Late Triassic to Early Jurassic of the United Kingdom. It is generally considered to be one of the most primitive members of the clade Rhynchocephalia. Description ''Gephyrosaurus bridensis'' was relatively small in size, with a skull around long, wide and deep. The skull of ''Gephyrosaurus bridensis'' lacks a complete temporal bar, with a gap between the jugal and quadrate bones. Unlike more advanced rhynchocephalians belonging to Sphenodontia, ''Gephyrosaurus bridensis'' retains a lacrimal bone in the skull, though it is considerably reduced in size compared to more primitive reptiles. The frontal and parietal bones are unpaired. Each half of the upper and lower jaws have around 35-40 teeth.Evans, S.E. 1980. The skull of a new eosuchian reptile from the Lower Jurassic of South Wales. ''Zoological Journal of the Linnean Society'' 70: 203–264. Unlike other known rhynchocephalians, all of these te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planocephalosaurus
''Planocephalosaurus'' is an extinct genus of basal rhynchocephalian. Fossils of the genus are primarily known from fissure fill deposits from the Late Triassic of southwest Britain, with fragmentary remains possibly belonging to the genus also known from the Late Triassic of Texas. Taxonomy The genus and the type species ''P. robinsonae'' was described in 1982 by Fraser from remains found in fissure fill deposits in Gloucestershire in southwest Britain. In 2004, a second species ''P. lucasi'' was described from remains found in the Tecovas Formation in Texas.Heckert, A. B. 2004. Late Triassic microvertebrates from the lower Chinle Group (Otischalkian-Adamanian: Carnian), southwestern U.S.A. New Mexico Museum of Natural History & Science Bulletin 27:1–170. ''P. robinsonae'' is known from disarticulated remains covering most of the skeleton,'','' while ''P. lucasi'' is known from fragments of the jaws. While originally classified in Sphenodontidae, later studies have placed it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Werner Janensch
Werner Ernst Martin Janensch (11 November 1878 – 20 October 1969) was a German paleontologist and geologist. Biography Janensch was born at Herzberg (Elster). In addition to Friedrich von Huene, Janensch was probably Germany's most important dinosaur specialist from the early and middle twentieth century. His most famous and significant contributions stemmed from the expedition undertaken to the Tendaguru Beds in what is now Tanzania. As leader of an expedition (together with Edwin Hennig) set up by the Museum für Naturkunde in Berlin, where he worked as a curator, Janensch helped uncover an enormous quantity of fossils of late Jurassic period dinosaurs, including several complete ''Brachiosaurus'' skeletons, then the largest animal ever known. During his long subsequent career (he worked in Berlin from 1914 to 1961), Janensch named several new dinosaur taxa including '' Dicraeosaurus'' (1914) and '' Elaphrosaurus'' (1920). Janensch's ''Brachiosaurus'' were later d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
