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Mesosaurus
''Mesosaurus'' (meaning "middle lizard") is an extinct genus of reptile from the Early Permian of southern Africa and South America. Along with it, the genera ''Brazilosaurus'' and '' Stereosternum'', it is a member of the family Mesosauridae and the order Mesosauria. ''Mesosaurus'' was long thought to have been one of the first marine reptiles, although new data suggests that at least those of Uruguay inhabited a hypersaline water body, rather than a typical marine environment. In any case, it had many adaptations to a fully aquatic lifestyle. It is usually considered to have been anapsid, although Friedrich von Huene considered it to be a synapsid, and this hypothesis has been revived recently. Discovery and naming The holotype of ''M. tenuidens'', MNHN 1865-77, is nicknamed the " Griqua ''Mesosaurus''" and it was found in a Griqua hut in South Africa, likely in Kimberley, Northern Cape around 1830 and was being used as a pot lid. The circumstances of its discovery and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereosternum Tumidum
''Stereosternum tumidum'' (meaning "rigid chest") (Stereos, Greek: “solid, firm”; Sternon, Greek: “chest, breastbone”) is an extinct genus of mesosaur marine reptile from the Early Permian of Brazil and also the Great Karoo Basin of South Africa.Oelofsen, B. W. and D. C. Araujo. "Mesosaurus Tenuidens and Stereosternum Tumidum from the Permian Gondwana of Both Southern Africa and South America." South African Journal of Science, vol. 83, no. 6, 01 June 1987, pp. 370-372. The taxon mesosaur is a monophyletic group containing '' Brazilosaurus sanpauloensis'' and ''Mesosaurus tenuidens''. For most of the 20th century, information of ''Stereosternum'' was reported as ''Mesosaurus''. Unlike previous interpretations of Mesosaurs as filter feeding animals, later studies have shown that these animals were very much active aquatic predators. ''Stereosternum'' and ''Mesosaurus'' are the oldest reported reptile species to have had a range spanning two present-day continents, then joi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesosaur
Mesosaurs ("middle lizards") were a group of small aquatic reptiles that lived during the early Permian period, roughly 299 to 270 million years ago. Mesosaurs were the first known aquatic reptiles, having apparently returned to an aquatic lifestyle from more terrestrial ancestors. It is uncertain which and how many terrestrial traits these ancestors displayed; recent research cannot establish with confidence if the first amniotes were fully terrestrial, or only amphibious. Most authors consider mesosaurs to have been aquatic, although adult animals may have been amphibious, rather than completely aquatic, as indicated by their moderate skeletal adaptations to a semiaquatic lifestyle.Pablo Nuñez Demarco et al. Was Mesosaurus a Fully Aquatic Reptile? Front. Ecol. Evol, published online July 27, 2018; doi: 10.3389/fevo.2018.00109 Similarly, their affinities are uncertain; they may have been among the most basal sauropsids or among the most basal parareptiles (in the case of w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. The earliest known proto-reptiles originated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Von Huene
Friedrich von Huene, born Friedrich Richard von Hoinigen, (March 22, 1875 – April 4, 1969) was a German paleontologist who renamed more dinosaurs in the early 20th century than anyone else in Europe. He also made key contributions about various Permo-Carboniferous limbed vertebrates. Biography Huene was born in Tübingen, Kingdom of Württemberg. His discoveries include the skeletons of more than 35 individuals of ''Plateosaurus'' in the famous Trossingen quarry, the early proto-dinosaur ''Saltopus'' in 1910, ''Proceratosaurus'' in 1926, the giant ''Antarctosaurus'' in 1929, and numerous other dinosaurs and fossilized animals like pterosaurs. He also was the first to naming several higher taxa, including Prosauropoda and Sauropodomorpha. In 1941 he found a stone that had petrified wood in it, sadly, He thought that it was a dinosaur. However a couple Polish paleontologists. The “dinosaur” was called the Succinodon He visited the Geopark of Paleorrota in 1928, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Reptile
Marine reptiles are reptiles which have become secondarily adapted for an aquatic or semiaquatic life in a marine environment. The earliest marine reptile mesosaurus (not to be confused with mosasaurus), arose in the Permian period during the Paleozoic era. During the Mesozoic era, many groups of reptiles became adapted to life in the seas, including such familiar clades as the ichthyosaurs, plesiosaurs (these two orders were once thought united in the group "Enaliosauria", a classification now cladistically obsolete), mosasaurs, nothosaurs, placodonts, sea turtles, thalattosaurs and thalattosuchians. Most marine reptile groups became extinct at the end of the Cretaceous period, but some still existed during the Cenozoic, most importantly the sea turtles. Other Cenozoic marine reptiles included the bothremydids, palaeophiid snakes, a few choristoderes such as '' Simoedosaurus'' and dyrosaurid crocodylomorphs. Various types of marine gavialid crocodilians remaine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anapsid
An anapsid is an amniote whose skull lacks one or more skull openings (fenestra, or fossae) near the temples. Traditionally, the Anapsida are the most primitive subclass of amniotes, the ancestral stock from which Synapsida and Diapsida evolved, making anapsids paraphyletic. It is however doubtful that all anapsids lack temporal fenestra as a primitive trait, and that all the groups traditionally seen as anapsids truly lacked fenestra. Anapsids and the turtles While "anapsid reptiles" or "anapsida" were traditionally spoken of as if they were a monophyletic group, it has been suggested that several groups of reptiles that had anapsid skulls might be only distantly related. Scientists still debate the exact relationship between the basal (original) reptiles that first appeared in the late Carboniferous, the various Permian reptiles that had anapsid skulls, and the Testudines (turtles, tortoises, and terrapins). However, it was later suggested that the anapsid-like turtle skull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermal Bone
A dermal bone or investing bone or membrane bone is a bony structure derived from intramembranous ossification forming components of the vertebrate skeleton including much of the skull, jaws, gill covers, shoulder girdle and fin spines rays ( lepidotrichia), and the shell (of tortoises and turtles). In contrast to endochondral bone, dermal bone does not form from cartilage that then calcifies, and it is often ornamented. Dermal bone is formed within the dermis and grows by accretion only – the outer portion of the bone is deposited by osteoblasts. The function of some dermal bone is conserved throughout vertebrates, although there is variation in shape and in the number of bones in the skull roof and postcranial structures. In bony fish, dermal bone is found in the fin rays and scales. A special example of dermal bone is the clavicle The clavicle, or collarbone, is a slender, S-shaped long bone approximately 6 inches (15 cm) long that serves as a strut between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleithrum
The cleithrum (plural cleithra) is a membrane bone which first appears as part of the skeleton in primitive bony fish, where it runs vertically along the scapula. Its name is derived from Greek κλειθρον = "key (lock)", by analogy with " clavicle" from Latin ''clavicula'' = "little key". In modern fishes, the cleithrum is a large bone that extends upwards from the base of the pectoral fin and anchors to the cranium above the gills, forming the posterior edge of the gill chamber. The bone has scientific use as a means to determine the age of fishes. The lobe-finned fishes share this arrangement. In the earliest amphibians however, the cleithrum/clavicle complex came free of the skull roof, allowing for a movable neck. The cleithrum disappeared early in the evolution of reptiles, and in amniotes is very small or absent. It has been argued based on position, muscle connectivity, and developmental origin that the nuchal element of the turtle carapace is formed from fused ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachyostosis
Pachyostosis is a non-pathological condition in vertebrate animals in which the bones experience a thickening, generally caused by extra layers of lamellar bone. It often occurs together with bone densification (osteosclerosis), reducing inner cavities. This joint occurrence is called pachyosteosclerosis. However, especially in the older literature, "pachyostosis" is often used loosely, referring to all osseous specializations characterized by an increase in bone compactness and/or volume. It occurs in both terrestrial and, especially, aquatic or semi-aquatic vertebrates. In aquatic animals, such as seacows (manatees and dugongs), ''Thalassocnus'', and plesiosaurs, pachyostosis in the thoracic region provides (or provided) ballast against the air-filled lungs. This maintains neutral buoyancy in aquatic habitats. Most giant deer showed pronounced pachyostosis of the mandible and skull. It has been suggested that this served to store minerals for antler growth. Many Pachycephalo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Griqua People
The Griquas (; af, Griekwa, often confused with ''!Orana'', which is written as ''Korana'' or ''Koranna'') are a subgroup of heterogeneous former Khoe-speaking nations in Southern Africa with a unique origin in the early history of the Cape Colony. Text was copied from this source, which is available under a Creative Commons license. Under apartheid, they were given a special racial classification under the broader category of " Coloured". Similar to the Trekboers (another Afrikaans-speaking group of the time), they originally populated the frontiers of the nascent Cape Colony (founded in 1652). The men of their semi-nomadic society formed commando units of mounted gunmen. Like the Boers, they migrated inland from the Cape, in the 19th century establishing several states in what are now South Africa and Namibia. Griqua was the name given to a mixed-race culture in the Cape Colony of South Africa, around the 17th and 18th Century (Taylor, 2020). They were also known as Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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