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Varanus Darevskii
''Varanus darevskii'', also known as the Central Asian monitor, is an extinct species of monitor lizard from the Early Pliocene of Tajikistan, known from a partial skull. ''V. darevskii'' might have been a close relative of, and perhaps ancestral to, the modern desert monitor (''V. griseus''). Discovery and naming ''Varanus darevskii'' was described by the Russian palaeontologist Irina Levshakova in 1986, based on a partial skull in comparatively good condition from the Early Pliocene found near the village of Sor in the Sughd Region of Tajikistan. The skull preserved the snout in its entirety, alongside portions of the skull roof and palate. The species name ''darevskii'' honors the Russian zoologist and herpetologist Ilya Darevsky. Levshakova also gave the species a common name, calling it the Central Asian monitor. Description The skull of ''V. darevskii'' is similar to the modern desert monitor (''V. griseus''), but differs by having a broader parietal region and a more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58See the 2014 version of the ICS geologic time scale million years ago. It is the second and most recent epoch of the Neogene Period in the . The Pliocene follows the Epoch and is followed by the Epoch. Prior to the 2009 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is , of which the eye occupies . The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and duct, the eyelids, medial and lateral palpebral ligaments, cheek ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves. Structure The orbits are conical or four-sided pyramidal cavities, which open into the midline of the face and point back into the head. Each consists of a base, an apex and four walls."eye, human."Encyclopædia Britannica from Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 2009 Openings There are two important foramina, or windows, two important fissu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Savannah Monitor
The savannah monitor (''Varanus exanthematicus'') is a medium-sized species of monitor lizard native to Africa. The species is known as Bosc's monitor in Europe, since French scientist Louis Bosc first described the species. It belongs to the subgenus '' Polydaedalus''. Etymology The specific name ''exanthematicus'' is derived from the Greek word ''exanthem'' , meaning an eruption or blister of the skin. French botanist and zoologist Louis Augustin Guillaume Bosc originally described this lizard as ''Lacerta exanthematica'' in reference to the large oval scales on the back of its neck. The species was formerly known as ''Lacerta exanthematicus''. Description Savannah monitors are stoutly built, with relatively short limbs and toes, and skulls and dentition adapted to feed on hard-shelled prey. They are robust creatures, with powerful limbs for digging, powerful jaws and blunt, peglike teeth. Maximum size is rarely more than 100 cm. The skin coloration pattern varies accor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock Monitor
The rock monitor (''Varanus albigularis'') is a species of monitor lizard in the family Varanidae. The species is endemic to Central, East, and southern Africa. It is the second-longest lizard found on the continent, and the heaviest-bodied; locally, it is called ''leguaan'' or ''likkewaan''. Taxonomy First described by François Marie Daudin in 1802, ''V. albigularis'' has been classified as a subspecies of '' V. exanthematicus'', Laurent RF (1964). "A new subspecies of ''Varanus exanthematicus'' (Sauria, Varanidae)". ''Breviora'' (199): 1-5. (''Varanus exanthematicus ionidesii'', new subspecies). but has since been declared a distinct species based upon differences in hemipenal morphology. The generic name ''Varanus'' is derived from the Arabic word ''waral'' ورل, which is translated to English as "monitor". The specific name ''albigularis'' comes from a compound of two Latin words: ''albus'' meaning "white" and ''gula'' meaning "throat". The subspecies of ''V. albi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nile Monitor
The Nile monitor (''Varanus niloticus'') is a large member of the monitor family (Varanidae) found throughout most of Sub-Saharan Africa and along the Nile, with invasive populations in North America. The population in West African forests and savannahs is sometimes recognized as a separate species, the West African Nile monitor (''V. stellatus'').Dowell, S.A, D.M. Portik, V. de Buffrenil, I Ineich, E Greenbaum, S.O. Kolokotronis and E.R. Hekkala. 2016. Molecular data from contemporary and historical collections reveal a complex story of cryptic diversification in the Varanus (Polydaedalus) niloticus Species Group. Molecular Phylogenetics and Evolution 94(Part B): 591-604. It is one of the largest lizards in the world reaching and even surpassing the perentie by size. Other common names include the African small-grain lizard, as well as iguana and various forms derived from it, such as guana, water leguaan or river leguaan (leguan, leguaan, and likkewaan mean monitor lizard in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanus (Polydaedalus)
''Polydaedalus'', commonly referred as African monitors, is one of the 11 subgenera of the genus '' Varanus''. Its species are native to Africa and West Asia, among which are some of the World's largest lizards. Description African monitors are typically medium-sized monitor lizards, with males being larger than females. Nile monitors usually measure in length and weighs around , with exceptionally large specimens exceeding in length and in mass, making it the World's fourth largest lizard after the Komodo dragon, Asian water monitor and Crocodile monitor. The Rock monitor is much bulkier and is larger on average, but has a slightly smaller maximum size of just more than long but still weighing over , rivalling the Perentie as the fifth in size. African monitors are characterized by their tall heads and nostrils positioned close to their eyes. Their jaws are short and equipped with round, thick teeth. African have long, muscular tails like all monitors. Evolution and ecolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetics
In biology, phylogenetics (; from Greek language, Greek wikt:φυλή, φυλή/wikt:φῦλον, φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, Protein, protein Amino acid, amino acid sequences, or Morphology (biology), morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanus Bengalensis
The Bengal monitor (''Varanus bengalensis''), also called the common Indian monitor, is a monitor lizard distributed widely in the Indian Subcontinent, as well as parts of Southeast Asia and West Asia. This large lizard is mainly a terrestrial animal, and its length ranges from about from the tip of the snout to the end of the tail. Young monitors may be more arboreal, but adults mainly hunt on the ground, preying mainly on arthropods, but also taking small terrestrial vertebrates, ground birds, eggs and fish. Although large Bengal monitors have few predators apart from humans who hunt them for meat, younger individuals are hunted by many predators. Description The Bengal monitor can reach 175 cm with a snout-to-vent length (SVL) of 75 cm and a tail of 100 cm. Males are generally larger than females. Heavy individuals may weigh nearly 7.2 kg. The populations of monitors in India and Sri Lanka differ in the scalation from those of Myanmar; these populatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanus Flavescens
The yellow monitor (''Varanus flavescens'') or golden monitor is a monitor lizard native to South Asia. Description The yellow monitor is a medium-sized monitor, measuring from snout to vent between 45 cm and 95 cm including the tail and weighing up to 1450 gm. It has subcorneal teeth, scarcely compressed. Its snout is short and convex, measuring a little less than the distance from the anterior border of the orbit to the anterior border of the ear; ''canthus rostralis'' distinct. Its nostril is an oblique slit, a little nearer to the end of the snout than to the orbit. The digits are short with the length of the fourth toe, measured from its articulation with the tarsus to the base of the claw, not exceeding the length of the femur. The tail of the yellow monitor is feebly compressed and keeled above. The head scales are small and subequal; the median series of supraocular scales slightly dilated transversely. The scales on upper surfaces are moderate, oval and k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanus Marathonensis
''Varanus marathonensis'', the Samos dragon, is an extinct species of monitor lizard from the middle to late Miocene of Greece and Spain, known from several specimens. A specimen consisting of a partial skull and several vertebrae was named ''Varanus amnhophilis'' in 2012 and placed in its own subgenus, ''Varaneades'', but a 2018 study found it to be a junior synonym of ''Varanus marathonensis''. Comparisons with other species of monitor lizards put its size between in length. The fossil was found in the Turolian-age Mytilini Formation on the island of Samos and is currently housed in the American Museum of Natural History. Discovery and naming ''Varanus marathonensis'' is known from several specimens. One specimen from Cerro de los Batallones, Spain, is currently the most complete fossil of any ''Varanus'' species yet discovered. The specimen "''V. amnhophilis''" is known from several bone fragments, including the right side of the braincase, a right quadrate bone, part of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoogeography
Zoogeography is the branch of the science of biogeography that is concerned with geographic distribution (present and past) of animal species. As a multifaceted field of study, zoogeography incorporates methods of molecular biology, genetics, morphology, phylogenetics, and Geographic information system, Geographic Information Systems (GIS) to delineate evolutionary events within defined regions of study around the globe. Once proposed by Alfred Russel Wallace, known to be the father of zoogeography, phylogenetic affinities can be quantified among zoogeographic regions, further elucidating the phenomena surrounding geographic distributions of organisms and explaining evolutionary relationships of taxa. Advancements in molecular biology and theory of evolution within zoological research has unraveled questions concerning speciation events and has expanded phylogenic relationships amongst taxa. Integration of phylogenetics with GIS provides a means for communicating evolutionary or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
