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Mosasaurs
Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Greek ' meaning 'lizard') comprise a group of extinct, large marine reptiles from the Late Cretaceous. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. They belong to the order Squamata, which includes lizards and snakes. Mosasaurs probably evolved from an extinct group of aquatic lizards known as aigialosaurs in the Earliest Late Cretaceous with 42 described genera. During the last 20 million years of the Cretaceous period (Turonian–Maastrichtian ages), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They themselves became extinct as a result of the K-Pg event at the end of the Cretaceous period, about 66 million years ago. Description Mosasaurs breathed air, were powerful swimmers, and were well-adapted to living in the warm, shallow inland seas prevalent during the Late Cretaceous period. Mosasaurs were so wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platecarpus Tympaniticus
''Platecarpus'' ("flat wrist") is an extinct genus of aquatic lizards belonging to the mosasaur family, living around 84–81 million years ago during the middle Santonian to early Campanian, of the Late Cretaceous period. Fossils have been found in the United States and possible specimens in Belgium and Africa. A well-preserved specimen of ''Platecarpus'' shows that it fed on moderate-sized fish, and it has been hypothesized to have fed on squid, and ammonites as well. Like other mosasaurs, it was initially thought to have swum in an eel-like fashion, although another study suggests that it swam more like modern sharks. An exceptionally well-preserved specimen of ''P. tympaniticus'' known as LACM 128319 shows skin impressions, pigments around the nostrils, bronchial tubes, and the presence of a high-profile tail fluke, showing that it and other mosasaurs did not necessarily have an eel-like swimming method, but were more powerful, fast swimmers. It is held in the Natural History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plioplatecarpinae
Plioplatecarpinae is a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "plioplatecarpines" and have been recovered from all continents, though the occurrences in Australia remain questionable. The subfamily includes the genera '' Latoplatecarpus'', ''Platecarpus'', '' Plioplatecarpus'' and ''Plesioplatecarpus''. Plioplatecarpines were small to medium-sized mosasaurs that were comparatively fast and agile compared to mosasaurs of other subfamilies. The first plioplatecarpines appear in the Turonian and are among the oldest of mosasaurs, and the clade persists throughout the Maastrichtian, a period of approximately 24 million years. The subfamily was seemingly heavily affected during a poorly understood middle-Campanian mosasaur extinction event and its genera appear to have faced competition from mosasaurine mosasaurs during the Maastrichtian, leading to a decline in numbers and in diver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halisaurinae
The Halisaurinae are a subfamily of mosasaurs, a group of Late Cretaceous marine lizards. They were small to medium-sized, ranging from just under 3 meters in ''Eonatator sternbergi'' to as much as 8 or 9 meters in ''Pluridens serpentis''. They tended to have relatively slender jaws and small, numerous teeth, suggesting a diet of small fish and other prey. Although the skeleton is primitive compared to other Mosasauridae in many respects, halisaurines had the distinctive hypocercal tail of other mosasaurids suggesting good swimming ability, and they persisted alongside other mosasaurs until the end of the Cretaceous. The earliest known remains of halisaurines occur in rocks of Santonian age and the subfamily persists until the latest Maastrichtian. Halisaurines are known from North and South America, Europe, Asia and Africa, indicating a more or less global distribution in the Late Cretaceous. Four genera are currently recognized: ''Eonatator'', '' Halisaurus'', '' Phosphorosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethysaurinae
The Tethysaurinae are a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "tethysaurines" and have been recovered from North America and Africa. Only two tethysaurine genera are known, '' Pannoniasaurus'' and '' Tethysaurus''. The genera '' Yaguarasaurus'' and '' Russellosaurus'' were previously considered tethysaurines until they were grouped with ''Romeosaurus'' in the new subfamily Yaguarasaurinae. A possible member of this clade (subfamily) is a mosasaur specimen known from a maxilla fragment, found in 1960 in the Czech Republic (then Czechoslovakia), in Dolní Újezd near Litomyšl. Like the closely related yaguarasaurines, all tethysaurines were plesiopedal (meaning primitive and not as well adapted to marine life as later mosasaurs). They generally retained relatively small sizes compared to later giant mosasaurs. The tethysaurines appeared during the Turonian and went extinct in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yaguarasaurinae
The Yaguarasaurinae are a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "yaguarasaurines" and have been recovered from North and South America and Europe. Three genera, ''Yaguarasaurus'', ''Russellosaurus'' and '' Romeosaurus'' are known. ''Yaguarasaurus'' and ''Russellosaurus'' were previously considered part of the Tethysaurinae until they were grouped with '' Romeosaurus'' as yaguarasaurines. Like the closely related tethysaurines, all yaguarasaurines were plesiopedal (meaning primitive and not as well adapted to marine life as later mosasaurs). They generally retained relatively small sizes compared to later giant mosasaurs, though ''Yaguarasaurus'' itself might have grown rather large. The yaguarasaurines appeared during the Turonian and might have survived into the Santonian, though they were extinct by the Campanian when more derived and hydropedal mosasaurs had appeared. The et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tylosaurinae
The Tylosaurinae are a subfamily of mosasaurs,Williston, S. W. 1897. Range and distribution of the mosasaurs with remarks on synonymy. ''Kansas University Quarterly'' 4(4):177-185. a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "tylosaurines" and have been recovered from every continent except for South America. The subfamily includes the genera ''Tylosaurus'', ''Taniwhasaurus'', '' Hainosaurus'' and '' Kaikaifilu'', although some scientists argue that only ''Tylosaurus'' and ''Taniwhasaurus'' should be included. Tylosaurines first appeared in the ConiacianEverhart MJ. 2005b. Earliest record of the genus ''Tylosaurus'' (Squamata; Mosasauridae) from the Fort Hays Limestone (Lower Coniacian) of western Kansas. ''Transactions'' 108 (3/4): 149-155. and gave rise to some of the largest mosasaurs within the genera ''Tylosaurus'' and ''Hainosaurus'' which came to dominate as apex predators in marine ecosystems throu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mosasaurinae
The Mosasaurinae are a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "mosasaurines" and their fossils have been recovered from every continent except for South America. The lineage first appears in the Turonian and thrived until the K-Pg mass extinction at the end of the Maastrichtian. They ranged in size from some of the smallest known mosasaurs ('' Carinodens'', 3–3.5 meters), to medium-sized taxa ('' Clidastes'', 6+ meters), to the largest of the mosasaurs ('' Mosasaurus hoffmannii'') potentially reaching about 13 m in length. Many genera of mosasaurines were either piscivorous or generalists, preying on fish and other marine reptiles, but one lineage, the Globidensini, evolved specialized crushing teeth, adapting to a diet of ammonites and/or marine turtles. Though represented by relatively small forms throughout the Turonian and Santonian, such as '' Clidastes'', the lineage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snake
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads ( cranial kinesis). To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional lung. Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca. Lizards have evolved elongate bodies without limbs or with greatly reduced limbs about twenty-five times independently via convergent evolution, leading to many lineages of legless lizards. These resemble snakes, but several common groups of legless lizards have eyelids and external ears, which snakes lack, although this rule is not universal (see Amphisbae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aigialosauridae
Aigialosauridae (from Greek, ''aigialos'' = "seashore" and ''sauros''= lizard) is a family of Late Cretaceous semiaquatic pythonomorph lizards closely related to the mosasaurs. Regarded by some paleontologists as a distinct monophyletic group and by others as an adaptive grade within the basal mosasauroids, recent molecular and morphological data suggests that they are the oldest known members of the lineage leading to the mosasaurs. The family is recognized as containing two species, normally classified into two genera; ''Aigialosaurus'' and '' Opetiosaurus''. When used as an adaptive grade rather than as an actual monophyletic group, many other basal mosasauroids of uncertain affinities are occasionally referred to as "aigialosaurs", such as the genera '' Komensaurus'', '' Haasiasaurus'', '' Carsosaurus'' and ''Dallasaurus'' and even entire mosasaur clades, such as the Tethysaurinae. The term "plesiopedal mosasaurs" or "mosasaurs with a plesiopedal limb condition" is a more fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squamata
Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,900 species, it is also the second-largest order of extant (living) vertebrates, after the perciform fish. Members of the order are distinguished by their skins, which bear horny scales or shields, and must periodically engage in molting. They also possess movable quadrate bones, making possible movement of the upper jaw relative to the neurocranium. This is particularly visible in snakes, which are able to open their mouths very wide to accommodate comparatively large prey. Squamata is the most variably sized order of reptiles, ranging from the dwarf gecko (''Sphaerodactylus ariasae'') to the Reticulated python (''Malayopython reticulatus'') and the now- extinct mosasaurs, which reached lengths over . Among other reptiles, squamates are most ... [...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 mamma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Reptile
Marine reptiles are reptiles which have become secondarily adapted for an aquatic or semiaquatic life in a marine environment. The earliest marine reptile mesosaurus (not to be confused with mosasaurus), arose in the Permian period during the Paleozoic era. During the Mesozoic era, many groups of reptiles became adapted to life in the seas, including such familiar clades as the ichthyosaurs, plesiosaurs (these two orders were once thought united in the group "Enaliosauria", a classification now cladistically obsolete), mosasaurs, nothosaurs, placodonts, sea turtles, thalattosaurs and thalattosuchians. Most marine reptile groups became extinct at the end of the Cretaceous period, but some still existed during the Cenozoic, most importantly the sea turtles. Other Cenozoic marine reptiles included the bothremydids, palaeophiid snakes, a few choristoderes such as '' Simoedosaurus'' and dyrosaurid crocodylomorphs. Various types of marine gavialid crocodilians remaine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
