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Alligatoroid
Alligatoroidea is one of three superfamilies of crocodylians, the other two being Crocodyloidea and Gavialoidea. Alligatoroidea evolved in the Late Cretaceous period, and consists of the alligators and caimans, as well as extinct members more closely related to the alligators than the two other groups. Evolution The superfamily Alligatoroidea is thought to have split from the crocodile-gharial lineage in the late Cretaceous, about 80 million years ago, but possibly as early as 100 million years ago based on molecular phylogenetics. ''Leidyosuchus'' of Alberta is the earliest known genus. Fossil alligatoroids have been found throughout Eurasia as land bridges across both the North Atlantic and the Bering Strait have connected North America to Eurasia during the Cretaceous, Paleogene, and Neogene periods. Alligators and caimans split in North America during the early Tertiary or late Cretaceous (about 53 million to about 65 million years ago) and the latter reached South Ameri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deinosuchus
''Deinosuchus'' () is an extinct genus of alligatoroid crocodilian, related to modern alligators and caimans, that lived 82 to 73 million years ago (Ma), during the late Cretaceous period. The name translates as "terrible crocodile" and is derived from the Greek ''deinos'' (δεινός), "terrible", and ''soukhos'' (σοῦχος), "crocodile". The first remains were discovered in North Carolina (United States) in the 1850s; the genus was named and described in 1909. Additional fragments were discovered in the 1940s and were later incorporated into an influential, though inaccurate, skull reconstruction at the American Museum of Natural History. Knowledge of ''Deinosuchus'' remains incomplete, but better cranial material found in recent years has expanded scientific understanding of this massive predator. Although ''Deinosuchus'' was far larger than any modern crocodile or alligator, with the largest adults measuring in total length, its overall appearance was fairly simi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplocynodontinae
''Diplocynodon'' is an extinct genus of alligatoroid that lived during the Paleocene to Middle Miocene in Europe. It looked very similar to the modern caiman in that it was small and had bony armour scutes covering its neck, back, belly, and tail. The longest ''Diplocynodon'' recovered was 4 feet in length and probably fed on small fish, frogs, and took insects when young. In the nineteenth century, ''D. steineri'' was named from Styria, Austria and ''D. styriacus'' was named from Austria and France. A third Austrian species, ''Enneodon ungeri'', was placed in its own genus. The Austrian and French species of ''Diplocynodon'' were synonymized with ''E. ungeri'' in 2011, and because the name ''Diplocynodon'' has priority over ''Enneodon'', the species is now called ''D. ungeri''. Other genera have recently been found to be synonymous with ''Diplocynodon''. ''Hispanochampsa muelleri'' of Spain was determined to be synonymous with ''Diplocynodon'' in 2006, and ''Baryphracta deponaie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodyloidea
Crocodyloidea is one of three superfamilies of crocodilians, the other two being Alligatoroidea and Gavialoidea, and it includes the crocodiles. Crocodyloidea may also include the extinct Mekosuchinae, native to Australasia from the Eocene to the Holocene, although this is disputed. Classification Cladistically, it is defined as ''Crocodylus niloticus'' (the Nile crocodile) and all crocodylians more closely related to ''C. niloticus'' than to either ''Alligator mississippiensis'' (the American alligator) or ''Gavialis gangeticus'' (the gharial). This is a stem-based taxon, stem-based definition for crocodiles Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant memb ..., and is more inclusive than the crown group Crocodylidae. As a crown group, Crocodylidae only includes the last common anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globidonta
Globidonta is a clade of alligatoroids that includes alligators, caimans, and closely related extinct forms. It is defined as a stem-based clade including ''Alligator mississippiensis'' (the American Alligator) and all forms more closely related to it than to ''Diplocynodon''. The group's fossil range extends back into the Late Cretaceous with early alligatoroids such as '' Albertochampsa'' and '' Brachychampsa''. Extinct globidontans were particularly common in North America and Eurasia, and their modern range also includes South America. Basal globidontans are characterized by their blunt snouts and bulbous teeth. Modern globidontans have flattened snouts and more conical teeth, and are seen as more generalized than earlier globidontans. Generalized forms are usually expected to be ancestral to more specialized forms rather than descendants of them, so it is unusual for basal members of the group to appear specialized. This seems to conflict with the "Law of the Unspecialized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leidyosuchus
''Leidyosuchus'' (meaning " Leidy's crocodile") is an extinct genus of alligatoroid from the Late Cretaceous of Alberta. It was named in 1907 by Lawrence Lambe, and the type species is ''L. canadensis''. It is known from a number of specimens from the middle Campanian age Dinosaur Park Formation. It was a medium-sized alligatorid, with a maximum skull length greater than 40 centimeters (16 in). A number of species had been assigned to this genus over the years, including: ''L. acutidentatus'' ( Sternberg, 1932), from the Paleocene of Saskatchewan; ''L. formidabilis'' (Erickson, 1976), from the Paleocene of North Dakota and Wyoming; ''L. gilmorei'' (Mook, 1942), from the Campanian of Alberta; ''L. multidentatus'' (Mook, 1930); ''L. riggsi'' (Schmidt, 1938); ''L. sternbergii'' ( Gilmore, 1910), from the Maastrichtian (Late Cretaceous) of Colorado, Montana, North Dakota, South Dakota, and Wyoming; and ''L. wilsoni'' (Mook, 1959), from the Eocene of Wyoming. However, in 1997 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialoidea
Gavialoidea is one of three superfamilies of crocodylians, the other two being Alligatoroidea and Crocodyloidea. Although many extinct species are known, only the gharial ''Gavialis gangeticus'' and the false gharial ''Tomistoma schlegelii'' are alive today, with ''Hanyusuchus'' having become extinct in the last few centuries. Extinct South American gavialoids likely dispersed in the mid Tertiary from Africa and Asia. Fossil remains of the Puerto Rican gavialoid '' Aktiogavialis puertorisensis'' were discovered in a cave located in San Sebastián, Puerto Rico and dated to the Oligocene. This individual is thought to have crossed the Atlantic coming from Africa, indicating that this species was able to withstand saltwater. Classification Gavialoidea is cladistically defined as ''Gavialis gangeticus'' (the gharial) and all crocodylians closer to it than to ''Alligator mississippiensis'' (the American alligator) or ''Crocodylus niloticus'' (the Nile crocodile). This is a stem-bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caimaninae
A caiman (also cayman as a variant spelling) is an alligatorid belonging to the subfamily Caimaninae, one of two primary lineages within the Alligatoridae family, the other being alligators. Caimans inhabit Mexico, Central and South America from marshes and swamps to mangrove rivers and lakes. They have scaly skin and live a fairly nocturnal existence. They are relatively small-sized crocodilians with an average maximum weight of depending on species, with the exception of the black caiman (''Melanosuchus niger''), which can grow more than in length and weigh in excess of 1,000 kg (2,200 Ib). The black caiman is the largest caiman species in the world and is found in the slow-moving rivers and lakes that surround the Amazon basin. The smallest species is the Cuvier's dwarf caiman (''Paleosuchus palpebrosus''), which grows to long. There are six different species of caiman found throughout the watery jungle habitats of Central and Southern America. The average length for most o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Alligator
The American alligator (''Alligator mississippiensis''), sometimes referred to colloquially as a gator or common alligator, is a large crocodilian reptile native to the Southeastern United States. It is one of the two extant species in the genus ''Alligator'', and is larger than the only other living alligator species, the Chinese alligator. Adult male American alligators measure in length, and can weigh up to , with unverified sizes of up to and weights of making it one of the largest members of the family Alligatoridae, alongside the black caiman. Females are smaller, measuring in length. The American alligator inhabits subtropical and tropical freshwater wetlands, such as marshes and cypress swamps, from southern Texas to North Carolina. It is distinguished from the sympatric American crocodile by its broader snout, with overlapping jaws and darker coloration, and is less tolerant of saltwater but more tolerant of cooler climates than the American crocodile, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caimans
A caiman (also cayman as a variant spelling) is an alligatorid belonging to the subfamily Caimaninae, one of two primary lineages within the Alligatoridae family, the other being alligators. Caimans inhabit Mexico, Central and South America from marshes and swamps to mangrove rivers and lakes. They have scaly skin and live a fairly nocturnal existence. They are relatively small-sized crocodilians with an average maximum weight of depending on species, with the exception of the black caiman (''Melanosuchus niger''), which can grow more than in length and weigh in excess of 1,000 kg (2,200 Ib). The black caiman is the largest caiman species in the world and is found in the slow-moving rivers and lakes that surround the Amazon basin. The smallest species is the Cuvier's dwarf caiman (''Paleosuchus palpebrosus''), which grows to long. There are six different species of caiman found throughout the watery jungle habitats of Central and Southern America. The average length for most o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alligator
An alligator is a large reptile in the Crocodilia order in the genus ''Alligator'' of the family Alligatoridae. The two extant species are the American alligator (''A. mississippiensis'') and the Chinese alligator (''A. sinensis''). Additionally, several extinct species of alligator are known from fossil remains. Alligators first appeared during the Oligocene epoch about 37 million years ago. The name "alligator" is probably an anglicized form of ', the Spanish term for "the lizard", which early Spanish explorers and settlers in Florida called the alligator. Later English spellings of the name included ''allagarta'' and ''alagarto''. Evolution Alligators and caimans split in North America during the early Tertiary or late Cretaceous (about 53 million to about 65 million years ago). The Chinese alligator split from the American alligator about 33 million years ago and probably descended from a lineage that crossed the Bering land bridge during the Neogene. The modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listrognathosuchus
''Listrognathosuchus'' is an extinct genus of alligatoroid crocodilian. Fossils date back to the middle Paleocene epoch. In 1997, the generic name replaced that of ''Leidyosuchus'' for the species ''L. multidentatus'' (now the type species of ''Listrognathosuchus''). ''"L." multidentalis'' was first described by Charles Mook in 1930 on the basis of the holotype AMNH 5179, consisting of a partial vertebral column, mandible, partial left ilium, and left tibia, found from a locality in Torrejon Arroyo, New Mexico (then referred to as the Torrejon beds, and now thought to be part of the Nacimiento Formation). Phylogenetics The fragmentary nature of the material referable to ''Listrognathosuchus'' have made it hard to classify within Crocodylia, but it is now thought to be a relatively basal alligatoroid. ''Listrognathosuchus'' is closely related to ''Borealosuchus'', a more basal eusuchian that is not an alligatoroid, but rather a close relative of a monophyletic group of which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylian
Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period (Cenomanian stage) and are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the order's total group, the clade Pseudosuchia, appeared about 250 million years ago in the Early Triassic period, and diversified during the Mesozoic era. The order Crocodilia includes the true crocodiles (family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae). Although the term 'crocodiles' is sometimes used to refer to all of these, crocodilians is a less ambiguous vernacular term for members of this group. Large, solidly built, lizard-like reptiles, crocodilians have long flattened snouts, laterally compressed tails, and eyes, ears, and nostrils at the top of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
