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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 septo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovoo (lizard)
''Ovoo gurvel'' is an extinct varanid lizard from the Late Cretaceous of Mongolia. It is one of the smallest and earliest monitor lizards. It was described in 2008. ''Ovoo'' possesses a pair of two small bones in its skull that are not seen in any other lizard. Description and history ''Ovoo'' is only known from a fossilized skull cataloged as IGM 3/767 and designated the holotype. The skull was discovered in 2001 near the rich Ukhaa Tolgod fossil site in a locality known as Little Ukhaa. The deposits at Little Uhhaa date back to the Campanian stage of the Late Cretaceous. The generic name is derived from the name of a type of cairn called ovoos that are found along roads near Little Ukhaa. The specific name, ''gurvel'', comes from the Mongolian word for lizard. ''Ovoo'' was very small compared to living monitor lizards, with the exception of the Short-tailed monitor. Nevertheless, the structures of its skull are very similar to those of living monitors. ''Ovoo'' shares many s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanidae
The Varanidae are a family of lizards in the superfamily Varanoidea within the Anguimorpha group. 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 ''et al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Djadochta Formation
The Djadochta Formation (sometimes transcribed and also known as Djadokhta, Djadokata, or Dzhadokhtskaya) is a highly fossiliferous geological formation situated in Central Asia, Gobi Desert, dating from the Late Cretaceous period, about 75 million to 71 million years ago. The type locality is the Bayn Dzak locality, famously known as the Flaming Cliffs. Dinosaur, mammal, and other reptile remains are among the fossils that have been recovered from the formation. Excavation history The Djadochta Formation was first documented and explored—though only a single locality—during paleontological expeditions of the American Museum of Natural History in 1922–1925, which were part of the Central Asiatic Expeditions. The expeditions were led by Roy Chapman Andrews, in company of Walter Willis Granger as chief paleontologist and field team. The team did extensive exploration at the Bayn Dzak (formerly Shabarakh Usu) region, which they nicknamed Flaming Cliffs given that at sunset th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cherminotus
''Cherminotus'' is an extinct genus of monitor 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 monitor lizard and has a longer snout than its closest relative, the living Earless monitor lizard. ''Cherminotus'' is also very similar in appearance to ''Aiolosaurus'', another monitor from the Cretaceous of Mongolia. Both monitors have a single hole in the lacrimal bone The lacrimal bone is a small and fragile bone of the facial skeleton; it is roughly the size of the little fingernail. It is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders. Several bony landmarks of ... called the lacrimal foramen. Other monitors and monito ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger 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, Australia and Ant ... [...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 (5–6 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 Cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monitor Lizards
Monitor lizards are lizards in the genus ''Varanus,'' the only extant genus in the family Varanidae. They are native to Africa, Asia, and Oceania, and one species is also found in the Americas as an invasive species. About 80 species are recognized. Monitor lizards have long necks, powerful tails and claws, and well-developed limbs. The adult length of extant species ranges from in some species, to over in the case of the Komodo dragon, though the extinct varanid known as megalania (''Varanus priscus'') may have been capable of reaching lengths more than . Most monitor species are terrestrial, but arboreal and semiaquatic monitors are also known. While most monitor lizards are carnivorous, eating eggs, smaller reptiles, fish, birds, insects, and small mammals, some also eat fruit and vegetation, depending on where they live. Distribution The various species cover a vast area, occurring through Africa, the Indian subcontinent, to China, the Ryukyu Islands in southern Japan, so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Lizards
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous Lepidosaurs Of Asia
Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, a concept in econometrics Music * ''Late'' (album), a 2000 album by The 77s * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late" (song), a song by Blue Angel * "Late", a song by Kanye West from ''Late Registration'' Other * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Late may refer to a person who is Dead See also * * * ''Lates'', a genus of fish in the lates perch family * Later (other) * Tardiness * Tardiness (scheduling) In scheduling, tardiness is a measure of a delay in exe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Radiation
An evolutionary radiation is an increase in taxonomic diversity that is caused by elevated rates of speciation, that may or may not be associated with an increase in morphological disparity. Radiations may affect one clade or many, and be rapid or gradual; where they are rapid, and driven by a single lineage's adaptation to their environment, they are termed adaptive radiations. Examples Perhaps the most familiar example of an evolutionary radiation is that of placental mammals immediately after the extinction of the non-avian dinosaurs at the end of the Cretaceous, about 66 million years ago. At that time, the placental mammals were mostly small, insect-eating animals similar in size and shape to modern shrews. By the Eocene (58–37 million years ago), they had evolved into such diverse forms as bats, whales, and horses. Other familiar radiations include the Avalon Explosion, the Cambrian Explosion, the Great Ordovician Biodiversification Event, the Carboniferous-Earliest Perm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earless Monitor Lizard
The earless monitor lizard (''Lanthanotus borneensis'') is a semiaquatic, brown lizard native to the Southeast Asian island of Borneo. It is the only living species in the family Lanthanotidae and it is related to the true monitor lizards. Taxonomy The earless monitor lizard was 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 recognized from the start and Steindachner placed it in its own family, Lanthanotidae. In 1899 George Albert Boulenger relegated it to the family Helodermatidae, together with the beaded lizards and gila monster. 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 they should be recognized as separate families. Both are part of a broader Anguimorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
