|
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] |
Platynota
Platynota is a polyphyletic group of anguimorph lizards and thus belongs to the order Squamata of the class Reptilia. Since it was named in 1839, it has included several groups, including monitor lizards, snakes, mosasaurs, and helodermatids. Its taxonomic use still varies, as it is sometimes considered equivalent to the group Varanoidea and other times viewed as a distinct group. It is phylogenetically defined as a clade containing Varanidae (the monitor lizards). It also includes many extinct species. Description Many skeletal features support the grouping of monitor lizards, helodermatids, and several extinct species in Platynota. All platynotans have a hinged upper jaw with widely spaced teeth, each having a large base, that erupt from behind existing teeth. The teeth are plicidentine, meaning that they have highly folded layers of dentine in their centers. Many have fused frontal and nasal bones on the top of their skulls (in other lizards, these bones are separated into pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telmasaurus
''Telmasaurus'' is an extinct genus of varanoid lizard from the 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'', ... of Mongolia. Fossils have been found from the Djadokhta Formation, Djadokha and Barun Goyot Formations that date between the early and middle Campanian stage from approximately 80 to 75 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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanotidae
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] |
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] |
Komodo Dragon
The Komodo dragon (''Varanus komodoensis''), also known as the Komodo monitor, is a member of the monitor lizard family Varanidae that is endemic to the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang. It is the largest extant species of lizard, growing to a maximum length of , and weighing up to . As a result of their size, Komodo dragons are apex predators, and dominate the ecosystems in which they live. Komodo dragons hunt and ambush prey including invertebrates, birds, and mammals. It has been claimed that they have a venomous bite; there are two glands in the lower jaw that secrete several toxic proteins. The biological significance of these proteins is disputed, but the glands have been shown to secrete an anticoagulant. Komodo dragons' group behavior in hunting is exceptional in the reptile world. The diet of Komodo dragons mainly consists of Javan rusa (''Rusa timorensis''), though they also eat considerable amounts of carrion. Komodo dragons also occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estesia
''Estesia'' (in honour of Richard Estes) is an extinct genus of Late Cretaceous anguimorph lizard found in the Gobi Desert in Mongolia. It was discovered in June 1990 by a joint expedition made up of Mongolian and American palaeontologists, and described in 1992 by Mark Norell, Malcolm McKenna and Michael Novacek. This animal is of interest to palaeontologists, not only because it is close to the lineage of modern Gila monsters (''Heloderma''), but also because its dentition shows evidence that it was venomous. The type species is ''E. mongoliensis'', after Mongolia, where it was found. Material Material for ''Estesia'' has been collected in various localities in the Gobi Desert, including the Barun Goyot Formation, the Djadochta Formation and Ukhaa Tolgod. *IGM M3/14 (holotype): A well-preserved skull with mandible, from Lizard Hill, Khulsan (Barun Goyot Formation) *IGM 3/15: Partial skeleton with associated braincase, from Khermeen Tsav (Barun Goyot Formation), discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lizard
Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia although some lizards are more closely related to these two excluded groups than they are to other lizards. Lizards range in size from chameleons and geckos a few centimeters long to the 3-meter-long Komodo dragon. Most lizards are quadrupedal, running with a strong side-to-side motion. Some lineages (known as "legless lizards"), have secondarily lost their legs, and have long snake-like bodies. Some such as the forest-dwelling ''Draco'' lizards are able to glide. They are often territorial, the males fighting off other males and signalling, often with bright colours, to attract mates and to intimidate rivals. Lizards are mainly carnivorous, often being sit-and-wait predators; many smaller species eat insects, while the Komodo eats mammals a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goanna
A goanna is any one of several species of lizards of the genus '' Varanus'' found in Australia and Southeast Asia. Around 70 species of ''Varanus'' are known, 25 of which are found in Australia. This varied group of carnivorous reptiles ranges greatly in size and fills several ecological niches. The goanna features prominently in Aboriginal mythology and Australian folklore. Being predatory lizards, goannas are often quite large, or at least bulky, with sharp teeth and claws. The largest is the perentie (''V. giganteus''), which can grow over in length. Not all goannas are so large; pygmy goannas may be smaller than the arm of an adult human. The smallest of these, the short-tailed monitor (''V. brevicauda''), reaches only in length. They survive on smaller prey, such as insects and mice. Goannas combine predatory and scavenging behaviours. They prey on any animal they can catch that is small enough to eat whole. They have been blamed by farmers for the death of sheep, tho ... [...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] |
Parasaniwidae
''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 In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ... as the valid authority on its validity. Despite this, the name ''Necrosaurus'' was the widely used na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeosaniwa
''Palaeosaniwa canadensis'' is an extinct species of carnivorous lizard from the late Cretaceous of North America. The name, given by Charles Whitney Gilmore in 1928, means "ancient ''Saniwa'' from Canada". Description ''Palaeosaniwa'' was roughly comparable to a large monitor lizard (Varanidae) in size. Measuring around in length, it is among the largest terrestrial lizards known from the Mesozoic era (though '' Asprosaurus'' may compete with it in size). Later study shows estimation with snout–vent length about for Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ... species. It is similar to modern varanid lizards (particularly the Komodo dragon) in having bladelike teeth with minute serrations. These teeth would have been effective for seizing and cutting lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaganaias
''Kaganaias'' (meaning ' Kaga water nymph') is an extinct genus of basal and oldest dolichosaur that lived in what is now Japan during the Early Cretaceous. ''Kaganaias'' was semi-aquatic and is the only known aquatic squamate known from before the Cenomanian stage of the Cretaceous. It is also the first to be found in an inland area, instead of on the coast where aquatic squamates are commonly found.Evans, S.E., Manabe, M., Noro, M., Isaji, S. & Yamaguchi, M. (2006). "A Long-Bodied Lizard From The Lower Cretaceous Of Japan." ''Palaeontology'', 49.6, 2006, pp. 1143–1165. Its generic name is derived from Kaga Province, the old name for the Ishikawa Prefecture where the specimens were found, while the species name ''hakusanensis'' comes from the mountain that gives its name to Hakusan the city near its find site. The geological formation in which the specimens were found, the Kuwajima Formation, stands alongside the Tetori River and has been the site of numerous other finds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Goanna")
