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Mesenosaurus
''Mesenosaurus'' is an extinct genus of amniote. It belongs to the family Varanopidae. This genus includes two species: the type species ''Mesenosaurus romeri'' from the middle Permian (upper Kazanian) Mezen River Basin of northern Russia, and ''Mesenosaurus efremovi'' from the early Permian (Artinskian) Richards Spur locality (Oklahoma, United States). ''M. romeri''’s stratigraphic range is the middle to late Guadalupian while ''M. efremovi''’s stratigraphic range is the Cisuralian. Etymology Famous Russian paleontologist, Ivan Efremov, established ''Mesenosaurus'' as a genus, and named it after its roots with the (literal translation is “lizard from Mezen”). ''Mesenosaurus efremovi'' was named in honor of Ivan Efremov, who erected the genus. Description ''Mesenosaurus'' are small sized varanopid synapsids. They are characterized by mainly cranial features. Many of the postcranial features of this genus have not been analyzed fully due to a lack of fossil evidence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesenosaurus Romeri Skull
''Mesenosaurus'' is an extinct genus of amniote. It belongs to the family Varanopidae. This genus includes two species: the type species ''Mesenosaurus romeri'' from the middle Permian (upper Kazanian) Mezen River Basin of northern Russia, and ''Mesenosaurus efremovi'' from the early Permian ( Artinskian) Richards Spur locality (Oklahoma, United States). ''M. romeri''’s stratigraphic range is the middle to late Guadalupian while ''M. efremovi''’s stratigraphic range is the Cisuralian. Etymology Famous Russian paleontologist, Ivan Efremov, established ''Mesenosaurus'' as a genus, and named it after its roots with the (literal translation is “lizard from Mezen”). ''Mesenosaurus efremovi'' was named in honor of Ivan Efremov, who erected the genus. Description ''Mesenosaurus'' are small sized varanopid synapsids. They are characterized by mainly cranial features. Many of the postcranial features of this genus have not been analyzed fully due to a lack of fossil eviden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanopidae
Varanopidae is an extinct family of amniotes that resembled monitor lizards and may have filled a similar niche, hence the name. Typically, they are considered synapsids that evolved from an ''Archaeothyris''-like synapsid in the Late Carboniferous. However, some recent studies have recovered them being taxonomically closer to diapsid reptiles. A varanopid from the latest Middle Permian ''Pristerognathus'' Assemblage Zone is the youngest known varanopid and the last member of the "pelycosaur" group of synapsids. Description No known varanopids developed a sail like ''Dimetrodon''. The length of known varanopids, including the tail, varies from . Varanopids already showed some advanced characteristics of true pelycosaurs such as their deep, narrow, elongated skulls. Their jaws were long and their teeth were sharp. However, they were still primitive by mammalian standards. They had long tails, lizard-like bodies, and thin legs. The varanopids were mostly carnivorous, but as they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richards Spur
Richards Spur is a Permian fossil locality located at the Dolese Brothers Limestone Quarry north of Lawton, Oklahoma. The locality preserves clay and mudstone fissure fills of a karst system eroded out of Ordovician limestone and dolomite, with the infilling dating to the Artinskian stage of the early Permian (Cisuralian), around 289 to 286 million years ago. Fossils of terrestrial animals are abundant and well-preserved, representing one of the most diverse Paleozoic tetrapod communities known. A common historical name for the site is Fort Sill, in reference to the nearby military base. Fossils were first reported at the quarry by workers in 1932, spurring a wave of collecting by local and international geologists. Early taxa of interest included the abundant reptile ''Captorhinus'' and microsaurs such as ''Cardiocephalus'' and ''Euryodus''. Later notable discoveries include ''Doleserpeton'' (one of the most lissamphibian-like Paleozoic tetrapods), the most diverse assortment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiacodontidae
Ophiacodontidae is an extinct family of early eupelycosaurs from the Carboniferous and Permian. ''Archaeothyris'', and '' Clepsydrops'' were among the earliest ophiacodontids, appearing in the Late Carboniferous. Ophiacodontids are among the most basal synapsids, an offshoot of the lineage which includes therapsids and their descendants, the mammals. The group became extinct by the Middle Permian, replaced by anomodonts, theriodonts, and the diapsid reptiles. Characteristics The lifestyle of ophiacodonts has long been controversial. Some studies suggested that they were semi-aquatic, and some even suggested a fairly aquatic lifestyle, but a recent study based on a quantitative inference model suggested that both '' Clepsydrops'' and ''Ophiacodon'' were terrestrial. Vertebral morphometric data also support, though ambiguously, a rather terrestrial lifestyle for ''Ophiacodon'', which could reach a length of . ''Archaeothyris'' may also have been terrestrial, but no detailed st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caseasauria
Caseasauria is one of the two main clades of early synapsids, the other being the Eupelycosauria. Caseasaurs are currently known only from the Late Carboniferous and the Permian, and include two superficially different families, the small insectivorous or carnivorous Eothyrididae, and the large, herbivorous Caseidae. These two groups share a number of specialised features associated with the morphology of the snout and external naris. The ancestor of caseasaurs can be traced back to an insect eating or an omnivorous reptile-like synapsid from the Pennsylvanian time of the Carboniferous, possibly resembling ''Archaeothyris'', the earliest known synapsid. The caseasaurs were abundant during the later part of the Early Permian, but by the Middle Permian caseasaur diversity declined because the group was outcompeted by the more successful therapsids. The last caseasaurs became extinct at the end of the Guadelupian (Middle Permian). Description Among the most conspicuous charact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amniota
Amniotes are a clade of tetrapod vertebrates that comprises sauropsids (including all reptiles and birds, and extinct parareptiles and non-avian dinosaurs) and synapsids (including pelycosaurs and therapsids such as mammals). They are distinguished from the other tetrapod clade — the amphibians — by the development of three extraembryonic membranes ( amnion for embryoic protection, chorion for gas exchange, and allantois for metabolic waste disposal or storage), thicker and more keratinized skin, and costal respiration (breathing by expanding/constricting the rib cage). All three main features listed above, namely the presence of an amniotic buffer, water-impermeable cutes and a robust respiratory system, are very important for amniotes to live on land as true terrestrial animals – the ability to reproduce in locations away from water bodies, better homeostasis in drier environments, and more efficient air respiration to power terrestrial locomotions, although they migh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Captorhinus
''Captorhinus'' (from el, καπτō , 'to gulp down' and el, ῥῑνός , 'nose') is an extinct genus of captorhinid reptiles that lived during the Permian period. Its remains are known from Oklahoma, Texas, Europe, India, the Pedra de Fogo Formation, Parnaíba Basin, Brazil and the Madumabisa Mudstone, Zambia. Description While there are several forms of ''Captorhinus'', there are three main species that are the best known. The previously mentioned ''Captorhinus aguti'' is the type species of ''Captorhinus'', but there is also a fair amount of material collected on ''Captorhinus magnus'' and ''Captorhinus laticeps''. The most distinguishable trait of ''Captorhinus'' is its namesake: the hooking of the snout from prominent ventral angulation of the premaxillary process. Other notable characteristics include the dorsally positioned alary process of the jugal on the medial surface and flushed with the orbital margin, the retroarticular process longer anteroposteriorly th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protorothyris Archeri
''Protorothyris'' is an extinct genus of Early Permian protorothyridid known from Texas and West Virginia of the United States. It was first named by Llewellyn Ivor Price in 1937 and the type species is ''Protorothyris archeri''. ''P. archeri'' is known from the holotype MCZ 1532, a three-dimensionally preserved skull and from the referred specimens, which come from four additional individuals, MCZ 2147-2150. All specimens were collected in the Cottonwood Creek site, from the Archer City Formation, Texas, dating to the Asselian stage of the Cisuralian epoch, about 299–294.6 million years ago. A second species, ''P. morani'', was first named by Alfred Sherwood Romer in 1952 with its own generic name, ''Melanothyris''. In 1973, J. Clark and Robert L. Carroll recombined ''P. morani'' as a ''Protorothyris'' species. It is known from the holotype CM 8617, a three-dimensionally preserved skull. It was collected in the Blacksville site, from the Washington Formatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. 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. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids ( reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ianthodon Schultzei
''Ianthodon'' is an extinct genus of basal haptodontiform synapsids from the Late Carboniferous about 304 million years ago. The taxon was discovered and named by Kissel & Reisz in 2004.Kissel, R. A. & Reisz, R. R. ''Synapsid fauna of the Upper Pennsylvanian Rock Lake Shale near Garnett, Kansas and the diversity pattern of early amniotes''. In G. Arratia, M. V. H. Wilson & R. Cloutier (eds.). ''Recent Advances in the Origin and Early Radiation of Vertebrates''. Verlag Dr. Friedrich Pfeil, 2004. The only species in the taxon, ''Ianthodon schultzei'', was found by separating it from a block that also contained the remains of ''Petrolacosaurus'' and ''Haptodus''. The evolutionary significance of the taxon wasn't realized until a publication in 2015. The fossil of this organism was discovered in Garnett, Kansas. Description ''Ianthodon'' was first named by Kissel & Reisz in 2004, and a more detailed specimen was reevaluated in 2014. This single juvenile skeleton with delicate bones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tseajaia Campi
''Tseajaia'' is an extinct genus of tetrapod. It was a basal diadectomorph that lived in the Permian of North America. The skeleton is that of a medium-sized, rather advanced reptile-like amphibian. In life it was about long and may have looked vaguely like an iguana, though slower and with a more amphibian foot without claws. The dentition was somewhat blunt, indicating herbivory or possibly omnivory. Classification ''Tseajaia'' was described from a single, fairly complete specimen and was given its own family by Robert L. Carroll. It was originally thought to be a Seymouriamorph. Additional finds allowing for a better taxonomic analysis indicate they belong in the Diadectomorpha, as the sister group to the large and more derived Diadectidae. ''Tseajaia'' itself being a fairly generalized form, gives a reasonable indication of the build and looks of the closest relatives of the amniotes.Berman, D.S, Sumida, S.S., and Lombard, R.E. (1992): Reinterpretation of the temporal an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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