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Anguinae
Anguinae is a subfamily of legless lizards in the family Anguidae, commonly called glass lizards, glass snakes or slow worms. The first two names come from the fact their tails easily break or snap off. Members of Anguinae are native to North America, Europe, Asia, and North Africa. Evolution They first appeared in Europe during the early Eocene, approximately 48.6 million years ago, originating from North American ancestors that crossed over from Greenland via the Thule Land Bridge and spread toward Asia sometime after the drying of the Turgai Strait at the beginning of the Oligocene, and then across the Bering Land Bridge to North America during the Miocene. Description Very vestigial hindlegs are present in '' Hyalosaurus'' and ''Pseudopus'', but are entirely absent in the other genera.Lavin, & Girman, D. J. (2019). Phylogenetic relationships and divergence dating in the Glass Lizards (Anguinae). Molecular Phylogenetics and Evolution., 133, 128–140. Members of the group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anguidae
Anguidae refers to a large and diverse family of lizards native to the Northern Hemisphere. Common characteristics of this group include a reduced supratemporal arch, striations on the medial faces of tooth crowns, osteoderms, and a lateral fold in the skin of most taxa. The group includes the slowworms, glass lizards, and alligator lizards, among others. The family is divided into two subfamilies (Anguinae and Gerrhonotinae), and contains about 87 species in 8 genera. Morphology and reproduction Anguids have hard osteoderms beneath their scales giving them an armored appearance. Many of the species have reduced or absent limbs, giving them a snake-like appearance, while others are fully limbed. Body type varies among species, with sizes ranging from 10 cm to 1.5 m. The group includes oviparous and viviparous species, both of which can be observed in a single genus at times. Feeding and habitat These lizards are known carnivorous or insectivorous foragers, feed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophisaurus
''Ophisaurus'' (from the Greek 'snake-lizard') is a genus of superficially snake-like lizards in the family Anguidae. Known as joint snakes, glass snakes, or glass lizards, they are so-named because their tails are easily broken; like many lizards, they have the ability to deter predation by dropping off part of the tail, which can break into several pieces, like glass. The tail remains mobile, distracting the predator, while the lizard becomes motionless, allowing eventual escape. This serious loss of body mass requires a considerable effort to replace, and can take years to do so. Despite this ability, the new tail is usually smaller than the original. Although most species have no legs, their head shapes, movable eyelids, and external ear openings identify them as lizards. A few species have very small, stub-like legs near their rear vents. These are vestigial organs, meaning they once served an evolved purpose but are no longer used. They reach lengths of up to , but abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anguis
SlowwormsThe "slow-" in slowworm is distinct from the English adjective ''slow'' ("not fast"); the word comes from Old English ''slāwyrm'', where ''slā-'' means "slowworm" and ''wyrm'' means "serpent, reptile". () (also called blindworms and hazelworms) are a small genus (''Anguis'') of snake-like legless lizards in the family Anguidae. The genus has several living species, including the common slowworm, the eastern slowworm, the Greek slowworm, the Peloponnese slowworm, and the Italian slowworm (''Anguis veronensis''). There are also known fossil species. Description Slowworms are typically grey-brown, with the females having a coppery sheen and two lateral black stripes, and the males displaying electric blue spots, particularly in the breeding season. They give birth to live young, which are about long at birth and generally have golden stripes. Slowworms are slow-moving and can be easily caught, which has given rise to the folk etymology that the "slow" in slowworm is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudopus
''Pseudopus'' is a genus of anguid lizards that are native to Eurasia. One extant species remains, the sheltopusik, with four fossil species. They are the most robust members of subfamily Anguinae. The oldest fossils of the group date to the Early Miocene, but there are possible Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ... records. Classification Genus ''Pseudopus'' *'' Pseudopus apodus'' – sheltopusik, Pallas's glass lizard, European legless lizard, European glass lizard *†''Pseudopus ahnikoviensis'' *†''Pseudopus laurillardi'' *†''Pseudopus pannonicus'' *†''Pseudopus rugosus'' References Anguids Lizards of Asia Lizards of Europe Lizard genera Reptile genera with one living species Taxa named by Blasius Merrem {{Lizard-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophisaurus Ventralis
The eastern glass lizard (''Ophisaurus ventralis'') is a species of legless lizard in the family Anguidae, endemic to the Southeastern United States. The streamlined, legless species is often confused with snakes. Glass Lizards differ from snakes as they possess a moveable eyelid and an external ear opening, both of which are absent in snakes. ''Ventralis'' comes from the Latin "venter" meaning belly; this is in reference to the snake-like movement. Description Adults of ''O. ventralis'' grow to in total length, although the head-body length is only at most. There are 99 or more scales along the lateral groove. In this species, no dark longitudinal stripes are present below the lateral groove or under the tail, and there is no distinct mid-dorsal stripe. The neck is marked with a series of mostly vertical, or highly irregular, white marks, with white markings on posterior corners of scales. Dorsally, older specimens have a pattern consisting of numerous longitudinal dark lines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ... Epoch. The Oligocene is the third and final epoch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. '' Panthera leo'' (lion) and '' Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestigial
Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on comparison with homologous features in related species. The emergence of vestigiality occurs by normal evolutionary processes, typically by loss of function of a feature that is no longer subject to positive selection pressures when it loses its value in a changing environment. The feature may be selected against more urgently when its function becomes definitively harmful, but if the lack of the feature provides no advantage, and its presence provides no disadvantage, the feature may not be phased out by natural selection and persist across species. Examples of vestigial structures (also called degenerate, atrophied, or rudimentary organs) are the loss of functional wings in island-dwelling birds; the human vomeronasal organ; and the hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. During the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bering Land Bridge
Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula. It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States and the Yukon in Canada. The area includes land lying on the North American Plate and Siberian land east of the Chersky Range. At certain times in prehistory, it formed a land bridge that was up to wide at its greatest extent and which covered an area as large as British Columbia and Alberta together, totaling approximately . Today, the only land that is visible from the central part of the Bering land bridge are the Diomede Islands, the Pribilof Islands of St. Paul and St. George, St. Lawrence Island, St. Matthew Island, and King Island. The term ''Beringia' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turgai Strait
The Turgai Sea, also known as the Turgay Sea, Turgai Strait, Obik Sea, Ural Sea or West Siberian Sea, was a large shallow body of salt water (an epicontinental or epeiric sea) during the Mesozoic through Cenozoic Eras. It extended north of the present-day Caspian Sea to the "paleo-Arctic" region, and was in existence from the Middle Jurassic to Oligocene, approximately 160 to 29 million years ago. The Turgai Sea was not absolutely continuous throughout this entire era, though it was a persistent and predominating feature in its region; it "fragmented southern Europe and southwestern Asia into many large islands, and separated Europe from Asia." The division of the Eurasian landmass by the Turgai Sea had the effect of isolating animal populations. One of the better known groups are the ceratopsian dinosaurs during the Cretaceous Period, which were restricted to Asia and western North America that were connected for much of the era. The existence of the Turgai Sea also restricted var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
