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Mosasauroid
Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Ancient Greek, 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 Aigialosauridae, aigialosaurs in the Late Cretaceous, 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 Pliosauridae, pliosaurs, mosasaurs became the dominant marine predators. They themselves became extinct as a result of the Cretaceous–Paleogene extinction event, 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 livi ... [...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 diver ... [...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 formal ... [...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 through ... [...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 the ... [...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'', '' Phosphorosaur ... [...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 mammals a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snake
Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), 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, altho ... [...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 close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesosaur
Mesosaurs ("middle lizards") were a group of small aquatic reptiles that lived during the early Permian period, roughly 299 to 270 million years ago. Mesosaurs were the first known aquatic reptiles, having apparently returned to an aquatic lifestyle from more terrestrial ancestors. It is uncertain which and how many terrestrial traits these ancestors displayed; recent research cannot establish with confidence if the first amniotes were fully terrestrial, or only amphibious. Most authors consider mesosaurs to have been aquatic, although adult animals may have been amphibious, rather than completely aquatic, as indicated by their moderate skeletal adaptations to a semiaquatic lifestyle.Pablo Nuñez Demarco et al. Was Mesosaurus a Fully Aquatic Reptile? Front. Ecol. Evol, published online July 27, 2018; doi: 10.3389/fevo.2018.00109 Similarly, their affinities are uncertain; they may have been among the most basal sauropsids or among the most basal parareptiles (in the case of whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turonian
The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous Epoch, or a stage in the Upper Cretaceous Series. It spans the time between 93.9 ± 0.8 Ma and 89.8 ± 1 Ma (million years ago). The Turonian is preceded by the Cenomanian Stage and underlies the Coniacian Stage. At the beginning of the Turonian an oceanic anoxic event (OAE 2) took place, also referred to as the Cenomanian-Turonian boundary event or the "Bonarelli Event". Stratigraphic definition The Turonian (French: ''Turonien'') was defined by the French paleontologist Alcide d'Orbigny (1802–1857) in 1842. Orbigny named it after the French city of Tours in the region of Touraine (department Indre-et-Loire), which is the original type locality. The base of the Turonian Stage is defined as the place where the ammonite species '' Watinoceras devonense'' first appears in the stratigraphic column. The official reference profile (the GSSP) for the base of the Turonian is located in the Roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
