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Gavialoid
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] |
Kentisuchus
''Kentisuchus'' is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from England and France that date back to the early Eocene. The genus has also been recorded from Ukraine, but it unclear whether specimens from Ukraine are referable to ''Kentisuchus''. Species The genus ''Kentisuchus'' was erected by Charles Mook in 1955 for the species ''"Crocodylus" toliapicus'', described by Richard Owen, in 1849. William Buckland named ''"Crocodylus" spenceri'' on the basis of a partial skull found from the Isle of Sheppey in Kent, England. In 1888 Richard Lydekker considered ''"C." toliapicus'' synonymous with ''"C." champsoides'' and ''"C." arduini'', named by De Zigno, and reapplied the name ''"C." spenceri'' to all of these species. The genus name ''Kentisuchus'' was constructed only after it was realized that these specimens were clearly distinct from the genus ''Crocodylus'' and that some specimens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aktiogavialis
''Aktiogavialis'' is an extinct genus of crocodylian that lived from the Oligocene until the Miocene in what is now the Caribbean. Two species have been described: ''Aktiogavialis puertoricensis'' from the Middle Oligocene of Puerto Rico and ''Aktiogavialis caribesi'' from the Huayquerian of the Late Miocene of Venezuela. As a typical gavialoid, ''Aktiogavialis'' followed the standard crocodilian body plan. An elongated, squat quadrupedal body terminated in a long, laterally flattened tail at one end, and a specialized, narrow snout at the other. As with the other members of its family, the snout of ''Aktiogavialis'' was extremely long and narrow, tapering into a thin structure past the eye sockets. Based on the fragmentary remains recovered, the species was differentiated from other members of its family by unique positioning and geometry of its skull elements. Phylogenetic analysis indicates its closest relatives were the extinct gavials ''Gryposuchus'' and ''Siquisiquesuchus''. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocepesuchus
''Ocepesuchus'' (meaning "Ocepe crocodile", in reference to the OCP, or Office Chérifien des Phosphates, a phosphate-mining company that participated in the excavation of the specimen) is an extinct genus of gavialoid crocodilian, related to modern gharials. It lived in the Late Cretaceous of Morocco. Described by Jouve and colleagues in 2008, the type species is ''O. eoafricanus'', with the specific name meaning "dawn African" in reference to its great age relative to other African crocodilians. ''Ocepesuchus'' had a long snout with a tubular shape, wider than high. It is the oldest known true crocodilian from Africa.Other crocodile-like animals from older strata in Africa, like ''Sarcosuchus'', are not true crocodilians, but related animals. ''Ocepesuchus'' is based on OCP DEK-GE 45, a crushed but mostly complete skull from late Maastrichtian (Late Cretaceous)-age rocks in the Oulad Abdoun Basin, in the vicinity of Khouribga, Morocco. The individual is interpreted as a small a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratomistoma
''Paratomistoma'' (meaning "next to or near ''Tomistoma''") is an extinct monospecific genus of gavialoid crocodylian. It is based on the holotype specimen CGM 42188, a partial posterior skull and lower jaw discovered at Wadi Hitan, Egypt, in Middle Eocene-age rocks of the Gehannam Formation. The skull is unfused but considered morphologically mature. ''Paratomistoma'' was named in 2000 by Christopher Brochu and Philip Gingerich; the type species is ''P. courti'' in honor of Nicholas Court, who found CGM 42188. They performed a phylogenetic analysis and found ''Paratomistoma'' to be a derived member of Tomistominae, related to the false gharial. It may have been a marine or coastal crocodilian. Below is a cladogram based morphological studies comparing skeletal features that shows ''Paratomistoma'' as a member of Tomistominae: Based on morphological studies of extinct taxa, the tomistomines were long thought to be classified as crocodiles and not closely relat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maroccosuchus
''Maroccosuchus zennaroi'' is an extinct gavialoid crocodylian from the Early Eocene of Morocco, traditionally regarded as a member of the subfamily Tomistominae. Below is a cladogram based on morphological studies comparing skeletal features that shows ''Maroccosuchus'' as a member of Tomistominae, related to the false gharial: Based on morphological studies of extinct taxa, the tomistomines were long thought to be classified as crocodiles and not closely related to gavialoids. However, recent molecular studies using DNA sequencing have consistently indicated that the false gharial (''Tomistoma'') (and by inference other related extinct forms in Tomistominae) actually belong to Gavialoidea (and Gavialidae). Below is a cladogram from a 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data that shows ''Maroccosuchus'' as an early-diverging gavialoid, more basal than the last common ancestor to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dollosuchoides
''Dollosuchoides'', colloquially known as the Crocodile of Maransart, is an extinct monospecific genus of gavialoid crocodilian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found in the Brussel Formation of Maransart, Belgium and date back to the middle Eocene. The holotype, IRScNB 482, was discovered in 1915 and it was prepared during 1926–1927 by M. Hubert, J. Mehschaert and M. Jean de Kleermaeker, and also in 1927, Louis Dollo had the holotype put on display in the Museum of Natural Sciences and he intended to describe the specimen but he died in 1931 before he was able to describe it and the specimen was eventually referred to '' Dollosuchus'' by Swinton (1937)Swinton, W. E. (1937)The Crocodile of Maransart (Dollosuchus dixoni [Owen]).''Mémoire'' 80: 3–46 until it was moved to its own genus by Brochu (2007). It is currently housed in the Gand Museum in Belgium. Phylogeny Below is a cladogram based morphological studies c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylia
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 t ... [...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] |
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] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the Atlanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistics
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
