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Telmasaurus
''Telmasaurus'' is an extinct genus of varanoid lizard from the Late Cretaceous of Mongolia. Fossils have been found from the Djadokha and Barun Goyot Formations that date between the early and middle Campanian stage from approximately 80 to 71 million years ago. The type species ''Telmasaurus grangeri'' was named in 1943. Description ''Telmasaurus grangeri'' was named in 1943 and is now known from several fossils. Only two skulls are known, and the snout region is missing from both. Based on the size of these skulls, ''Telmasaurus'' was larger than other Cretaceous varanoid lizards, approaching the size of modern monitor lizards. Its skull is flatter than most other varanoids. The fusion of two bones in the skull called frontals links ''Telmasaurus'' with other early varanids like '' Paravaranus''. The lacrimal bone of ''Telmasaurus'' has a single hole in it, as do those of other early varanoids. The vertebrae of ''Telmasaurus'' are also known, and the way they attach to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanidae
The Varanidae are a family of lizards in the superfamily Varanoidea and order Anguimorpha. The family, a group of carnivorous and frugivorous lizards, includes the living genus '' Varanus'' and a number of extinct genera more closely related to ''Varanus'' than to the earless monitor lizard (''Lanthanotus''). ''Varanus'' includes the Komodo dragon (the largest living lizard), crocodile monitor, savannah monitor, the goannas of Australia and Southeast Asia, and various other species with a similarly distinctive appearance. Their closest living relatives are the earless monitor lizard and Chinese crocodile lizard. The oldest members of the family are known from the Late Cretaceous of Mongolia. Taxonomy The Varanidae were defined (using morphological characteristics) by Estes, de Queiroz and Gauthier (1988) as the clade containing the most recent common ancestor of '' Lanthanotus'' and ''Varanus'' and all of its descendants. A similar definition was formulated by Conrad ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saniwa
''Saniwa'' is an extinct genus of varanid lizard that lived during the Eocene epoch. It is known from well-preserved fossils found in the Bridger and Green River Formations of Wyoming, United States. The type species ''S. ensidens'' was described in 1870 as the first fossil lizard known from North America. A second species, ''S.'' ''orsmaelensis'', is recognised from remains found in Europe. It is a close relative of '' Varanus'', the genus that includes monitor lizards. Description ''Saniwa'' measured . Like other varanid lizards, ''Saniwa'' had a long, pointed snout and nostrils placed farther back in the skull than most lizards and a tail that was almost twice as long as the body. Although similar in appearance to extant monitor lizards, ''Saniwa'' had many primitive traits, including teeth on its palate, a jugal bone beneath the eye that extended farther forward, and a suture between the frontal and parietal bones that was straight rather than curved. A study in 2018 by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanoidea
Varanoidea is a superfamily of lizards, including the well-known family Varanidae (the monitors and goannas). Also included in the Varanoidea are the Lanthanotidae ( earless monitor lizards), and the extinct Palaeovaranidae. Throughout their long evolutionary history, varanoids have exhibited great diversity, both in habitat and form. This superfamily includes the largest-known terrestrial lizard, Megalania (~5 meters), and the largest extant lizard, the Komodo dragon (''Varanus komodoensis'', ~3 meters). Evolution Either synonymous with, or a subgroup of, the group Platynota, the varanoids first appear in the fossil record in the latter part of Early Cretaceous, but possible varanoid ancestors have been traced back as far as Early Jurassic times. Among the earliest known varanoids are the monitor-like necrosaurids '' Palaeosaniwa canadensis'' from the Campanian (roughly 71–82 mya) of North America and '' Estesia mongoliensis'' and '' Telmasaurus grangeri'', both from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necrosaurus
''Palaeovaranus'' is an extinct genus of varanoid lizards from the Late Eocene of France and Germany. It contains two species, ''Palaeovaranus cayluxensis'' and ''Palaeovaranus giganteus'' (formerly assigned to a separate genus ''Melanosauroides''). The genus was first named by Henri Filhol in 1877, but he had named the species ''Palaeovaranus cayluxi'' earlier as ''Palaeosaurus cayluxi'' in 1873, and as ''Necrosaurus cuxleyi'' in 1876 after it was discovered that ''Palaeosaurus'' was preoccupied. However, he failed to provide any kind of valid description, which renders Karl Alfred Ritter von Zittel's 1887 description of the taxon as the valid authority on its validity. Despite this, the name ''Necrosaurus'' was the widely used name in the literature afterwards until 2017, when the name ''Palaeovaranus'' was revived. It is placed in the family Palaeovaranidae. References External links † A dagger, obelisk, or obelus is a typographical mark that usually ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mosasaur
Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Ancient Greek, Greek ' meaning 'lizard') are an extinct group of large aquatic reptiles within the family Mosasauridae that lived during the Late Cretaceous. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. They belong to the order Squamata, which includes lizards and snakes. During the last 20 million years of the Cretaceous period (Turonian–Maastrichtian ages), with the extinction of the ichthyosaurs and Pliosauridae, pliosaurs, mosasaurids became the dominant marine predators. They themselves became extinct as a result of the Cretaceous–Paleogene extinction event, K-Pg event at the end of the Cretaceous period, about 66 million years ago. Description Mosasaurs breathed air, were powerful swimmers, and were well-adapted to living in the warm, shallow Inland sea (geology), inland seas prevalent during the Late Cretaceous period. Mosasaurs were so well adapted to thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aiolosaurus
''Aiolosaurus'' is an extinct genus of monitor lizard from the Late Cretaceous of Mongolia. The type and only species, ''Aiolosaurus oriens'', was named in 2000 from Ukhaa Tolgod, a rich fossil site in the Campanian-age Djadochta Formation. Description and history ''Aiolosaurus'' was named in 2000 on the basis of a single holotype specimen cataloged as IGM 3/171. This specimen includes a partial skull and parts of the postcranial skeleton. ''Aiolosaurus'' is named after Aeolus, the Greek god of wind, while the specific name of ''A. oriens'' means "east." Diagnostic features of ''Aiolosaurus'' are found mainly in the skull. They include: *The division of the nasals into two bones (they form one bone in living monitors). *A small hole in the snout between the premaxilla and maxilla bones called the premaxillary fenestra. *The separation of the premaxilla and septomaxilla bones by a projection of the maxilla bone. *The small size of another hole in the snout called the sept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanotus
The earless monitor lizard (''Lanthanotus borneensis'') is a semiaquatic, brown lizard native to the Southeast Asian island of Borneo. It is the monotypic, only living species in the family Lanthanotidae and it is related to the true monitor lizards. Taxonomy The earless monitor lizard was species description, described in 1878 by Franz Steindachner. The genus name ''Lanthanotus'' means "hidden ear" and the species name ''borneensis'' refers to its home island of Borneo. The uniqueness of the species was immediately recognized and Steindachner placed it in its own family, Lanthanotidae. In 1899, George Albert Boulenger relegated it to the family Helodermatidae, together with the Heloderma, beaded lizards and Gila monster, on the basis of morphological similarities. Further studies were conducted in the 1950s where it was found that although it is related to Helodermatidae, this relationship is relatively distant. The similarity is in part the result of convergent evolution and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cherminotus
''Cherminotus'' is an extinct genus of varanoid lizard from the Late Cretaceous of Mongolia. The type and only species, ''Cherminotus longifrons'', was named in 1984. Description and history ''Cherminotus longifrons'' was first described in 1984 from the Barun Goyot Formation. More specimens were later found in the Djadokhta Formation in localities such as Ukhaa Tolgod. ''Cherminotus'' is small for a varanoid and has a longer snout than its closest living relative, the Earless monitor lizard. ''Cherminotus'' is also very similar in appearance to ''Aiolosaurus'', another varanoid from the Cretaceous of Mongolia. Both lizards have a single hole in the lacrimal bone called the lacrimal foramen. Other varanoids have two holes in the lacrimal, making the presence of only one hole in ''Cherminotus'' a case of evolutionary reversal. References † A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
