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Rhineuridae
Rhineuridae is a family of amphisbaenians (commonly called worm lizards) that includes one living genus and species, '' Rhineura floridana'', as well as many extinct species belonging to both ''Rhineura'' and several extinct genera. The living ''R. floridana'' is found only in Georgia and Florida, but extinct species ranged across North America, some occurring as far west as Oregon. The family has a fossil record stretching back 60 million years to the Paleocene and was most diverse in the continental interior during the Eocene and Oligocene. Fossil record The fossil record of the Rhineuridae extends back almost to the Mesozoic, with the oldest rhineurid, '' Plesiorhineura tsentasai'', occurring in the Early Paleocene. ''Plesiorhineura'' is only known from a partial jaw, but it shares many features with modern rhineurids. Eocene rhineurids, such as '' Spathorhynchus fossorium'', are remarkably similar to the modern ''Rhineura'', suggesting very conservative evolution within the fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphisbaenia
Amphisbaenia (called amphisbaenians or worm lizards) is a group of typically legless lizards, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As many species have a pink body and scales arranged in rings, they have a superficial resemblance to earthworms. While the genus '' Bipes'' retains forelimbs, all other genera are limbless. Phylogenetic studies suggest that they are nested within Lacertoidea, closely related to the lizard family Lacertidae. Amphisbaenians are widely distributed, occurring in North America, Europe, Africa, South America, Western Asia and the Caribbean. Most species are less than long. Description 200px, left, Close-up of the head of'' Rhineura'' Despite a superficial resemblance to some primitive snakes, amphisbaenians have many unique features that distinguish them from other reptiles. Internally, their right lung is reduced in size to fit their narrow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaerhineura
''Archaerhineura'' was a genus of amphisbaenian lizards in the family Rhineuridae that is now extinct. The only species is ''Archaerhineura mephitis'', named in 2015 on the basis of a single fragment of the lower jaw from the Polecat Bench Formation in Park County, Wyoming, which dates to the late Paleocene (about 57 to 58 million years ago). ''Archaerhineura'' is one of the oldest amphisbaenians and was part of an evolutionary radiation of Rhineuridae in the Paleocene several million years after the Cretaceous–Paleogene extinction event (the only surviving member of Rhineuridae is ''Rhineura floridana'', which lives in Florida). This rhineurid radiation coincided with the radiation of another group of amphisbaenians, Amphisbaeniformes, which includes the still-extant families Blanidae and Amphisbaenidae. The presence of ''Archaerhineura'' and other Paleocene rhineurids in the western United States indicates that amphisbaenians, which would later have a nearly global distributio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrorhineura
''Macrorhineura'' is an extinct genus of rhineurid amphisbaenian or worm lizard, including the type and only species ''Macrorhineura skinneri'', named in 1970 on the basis of the front half of a skull from the Early Miocene Sharps Formation in Wounded Knee, South Dakota. Although the skull is incomplete, features such as a pointed, shovel-shaped snout indicate that it belongs to the family Rhineuridae. Within Rhineuridae, ''Macrorhineura'' is most closely related to '' Ototriton'' and '' Hyporhina'', two genera from the Eocene and Oligocene of Colorado and Wyoming, based on the shared feature of equally sized dentary teeth in the lower jaw. Together they form a clade or evolutionary grouping of mid-continental rhineurids, which became isolated from a more western clade of rhineurids that includes ''Dyticonastis'' and ''Spathorhynchus''. Rhineurids were relatively common across much of North America during the Paleogene, but their range contracted in the Neogene as the climate be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyticonastis
''Dyticonastis'' is an extinct genus of amphisbaenians, or worm lizards, that includes a single species, ''Dyticonastis rensbergeri'', that lived during the late Oligocene and early Miocene in what is now Oregon. Fossils of the species come from the John Day Formation. It belongs to Rhineuridae, a family that includes many other extinct North American amphisbaenians but only one living species, ''Rhineura floridana'', from Florida. ''Dyticonastis rensbergeri'' occurs the farthest west of all rhineurid species. Like all rhineurids, ''Dyticonastis'' has a shovel-like snout adapted for burrowing underground, but it differs from most other members of the group in having a relatively shallow angle to its snout wedge (about 30 degrees) and in having a widened snout tip. The only other rhineurids that share these features are species of the genus ''Spathorhynchus'', which lived from the Middle Eocene to the Early Oligocene in what is now Wyoming. A 2007, phylogenetic analysis of amphisba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyporhina
''Hyporhina'' is an extinct genus of amphisbaenians or worm lizards that lived from the Late Eocene to the Middle Oligocene (approximately 40 to 30 million years ago) in what is now the western United States. Species It currently includes two species, both from the White River Formation in eastern Wyoming and northeastern Colorado: * ''Hyporhina antiqua'' — the type species. * ''Hyporhina galbreathi'' * ''Hyporhina tertia'' — a third species named in 1972, and later synonymized with ''Hyporhina galbreathi''. Taxonomy Paleontologist Georg Baur named the genus ''Hyporhina'' in 1893, making it one of the first prehistoric amphisbaenians to be described. Baur placed it in its own family, Hyporhinidae, because it possessed eye sockets that are enclosed at the back by postorbital bars, a feature that living amphisbaenians lack. However, more recent studies have placed it within Rhineuridae, a family that includes the living ''Rhineura floridana ''Rhineura floridana'', known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spathorhynchus Fossorium
''Spathorhynchus'' is an extinct genus of amphisbaenians or worm lizards that existed from the Middle Eocene to the Early Oligocene in what is now Wyoming. It includes two species, the type species ''S. fossorium'', named in 1973 from the Middle Eocene Bridger and Wind River Formations, and the species ''S. natronicus'', named in 1977 from the Lower Oligocene White River Formation. ''Spathorhynchus'' belongs to the family Rhineuridae, which includes many other extinct species that ranged across North America at various times in the Cenozoic but only has one surviving member, ''Rhineura floridana'', from Florida. ''Spathorhynchus'' differs from all other rhineurids except ''Dyticonastis'' from the Late Oligocene-Early Miocene of Oregon in having a slightly widened, spatula-shaped snout tip with a low angle of about 30 degrees. The two taxa may be closely related, having evolved in isolation in western North America after the formation of the Rocky Mountains The Rocky Mountain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhineura Floridana
''Rhineura floridana'', known commonly as the Florida worm lizard, graveyard snake, or thunderworm, is a species of amphisbaenian in the family Rhineuridae. The species is the only extant member of the genus ''Rhineura'', and is found primarily in Florida but has been recorded in Lanier County, Georgia. There are no subspecies that are recognized as being valid. Description ''R. floridana'' varies in total length (including tail) from . The head has a shovel-like snout that projects forward past the lower jaws, which is used for burrowing. The eyes are highly reduced and not visible externally. The limbs are absent and, as in other Amphisbaenia, the body is covered by scales arranged in rings giving the animal a worm-like appearance. Habitat The preferred natural habitats of ''R. floridana'' are forest and shrubland. More specifically, in xeric and mesic hammocks around northeastern and central Florida. Southern populations have been shown to prefer xeric hammocks. Behavior '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ototriton
''Ototriton'' is an extinct genus of rhineurid amphisbaenian or worm lizard from the Early Eocene of the western United States, including the type and only species ''Ototriton solidus''. Paleontologist F. B. Loomis named ''Ototriton'' in 1919 on the basis of a single skull from the Wind River Formation in Wyoming, misinterpreting it as the skull of a salamander. Unlike salamanders and like other rhineurids, ''Ototriton'' has a shovel-shaped snout that it presumably used for burrowing underground. ''Ototriton'' is one of the earliest known rhineurids and also one of the largest. Several other species have been assigned to ''Ototriton'' since Loomis named the genus in 1919. In 1928, paleontologist Charles W. Gilmore assigned a vertebra from the Bridger Formation of Wyoming, first classified as '' Glyptosaurus anceps'', to ''Ototriton'' based on its large size, but later attributed it to the snake '' Lestophis crassus''. In 1945, Gilmore and G. I. Jepsen named a new species of ''Ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synonym (taxonomy)
In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The Botanical nomenclature, botanical and Zoological nomenclature, zoological codes of nomenclature treat the concept of synonymy differently. * In nomenclature, botanical nomenclature, a synonym is a Binomial nomenclature, scientific name that applies to a taxon that now goes by a different scientific name. For example, Carl Linnaeus, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different Binomial nomenclature, binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Miocene Disruption
The Middle Miocene Climatic Transition (MMCT) was a relatively steady period of climatic cooling that occurred around the middle of the Miocene, roughly 14 million years ago (Ma), during the Langhian stage, and resulted in the growth of ice sheet volumes globally, and the reestablishment of the ice of the East Antarctic Ice Sheet (EAIS). The term Middle Miocene disruption, alternatively the Middle Miocene extinction or Middle Miocene extinction peak, refers to a wave of extinctions of terrestrial and aquatic life forms that occurred during this climatic interval. This period was preceded by the Middle Miocene Climatic Optimum (MMCO), a period of relative warmth from 18 to 14 Ma. Cooling that led to the Middle Miocene disruption is primarily attributed CO2 being pulled out of the Earth's atmosphere by organic material before becoming caught in different locations like the Monterey Formation. These may have been amplified by changes in oceanic and atmospheric circulation due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
