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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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrorhineura Skinneri
''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] |
Rhineurid
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 fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sharps Formation
The Sharps Formation is a Formation (geology), geologic formation in South Dakota. It preserves fossils dating back to the Paleogene. The Sharps Formation is the namesake of the community of Sharps Corner, South Dakota. Fossil content Mammals Carnivorans Eulipotyphlans Lagomorphs Metatherians Primates Rodents Ungulates Reptiles Squamates See also * List of fossiliferous stratigraphic units in South Dakota * Paleontology in South Dakota References * Paleogene geology of South Dakota {{Paleogene-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Miocene
The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was preceded by the Oligocene epoch. As the climate started to get cooler, the landscape started to change. New mammals evolved to replace the extinct animals of the Oligocene epoch. The first members of the hyena and weasel family started to evolve to replace the extinct '' Hyaenodon'', entelodonts and bear-dogs. The chalicotheres survived the Oligocene epoch. A new genus of entelodont called '' Daeodon'' evolved in order to adapt to the new habitats and hunt the new prey animals of the Early Miocene epoch; it quickly became the top predator of North America. But it became extinct due to competition from ''Amphicyon ''Amphicyon'' ("ambiguous dog") is an extinct genus of large carnivorous bone-crushing mammals, popularly known as bear dogs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene Reptiles Of North America
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 late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene Lepidosaurs
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 late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphisbaenians
Amphisbaenia (called amphisbaenians or worm lizards) is a group of usually legless squamates, 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 (lizard), Bipes'' retains forelimbs, all other genera are limbless. Although superficially similar to the snakes and Dibamidae, blind lizards, recent phylogenetic studies suggest that they are most closely related to Podarcis, wall lizards of the 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 image:Amphisbaenia 1.jpg, 200px, left, Close-up of the head of'' Rhineura'' Despite a superficial resemblance to some primitive snakes, amphisbaenians have many unique fea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhineura Floridana
''Rhineura floridana'', known commonly as the Florida worm lizard, graveyard snake, Goin CJ, Goin OB, Zug GR (1978). ''Introduction to Herpetology, Third Edition''. San Francisco: W.H. Freeman and Company. xi + 378 pp. . (''Rhineura floridana'', p. 277, Figure 15-2). or thunderworm, is a species of amphisbaeninan 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'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago (Mya) to the beginning of the present Quaternary Period Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene. Some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes (1815–1868). During this period, mammals and birds continued to evolve into modern forms, while other groups of life remained relatively unchanged. The first humans ('' Homo habilis'') appeared in Africa near the end of the period. Some continental movements took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the warm ocean currents from the Pacific t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene
The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago (Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the Cretaceous–Paleogene extinction event that ended the preceding C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spathorhynchus
''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 Mountains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
