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Crocodylidae
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 members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological families. The gharial, with its narrow snout, is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteolaeminae
Osteolaeminae is a subfamily of true crocodiles within the family Crocodylidae containing the dwarf crocodiles and slender-snouted crocodiles, and is the sister taxon to Crocodylinae. Taxonomy Osteolaeminae was named by Christopher Brochu in 2003 as a subfamily of Crocodylidae separate from Crocodylinae, and is cladistically defined as ''Osteolaemus tetraspis'' (the Dwarf crocodile) and all crocodylians more closely related to it than to ''Crocodylus niloticus'' (the Nile crocodile). This is a stem-based definition, and is the sister taxon to Crocodylinae. Osteolaeminae contains the two extant genera ''Osteolaemus'' and ''Mecistops'', along with several extinct genera, although the number of extant species within Osteolaeminae is currently in question. Phylogeny The cladogram below is based on two studies that combined morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data. Alternatively, other morphological studies have recovered ''Mecistops'' a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylus
''Crocodylus'' is a genus of true crocodiles in the family Crocodylidae. Taxonomy The generic name, ''Crocodylus'', was proposed by Josephus Nicolaus Laurenti in 1768. ''Crocodylus'' contains 13–14 extant (living) species and 5 extinct species. There are additional extinct species attributed to the genus ''Crocodylus'' that studies have shown no longer belong, although they have not yet been reassigned to new genera. Extant species The 13–14 living species are: Fossils ''Crocodylus'' also includes five extinct species: * † '' Crocodylus anthropophagus'' is an extinct crocodile from Plio-Pleistocene of Tanzania. * † ''Crocodylus checchiai'' is an extinct crocodile from Late Miocene of Kenya. * † ''Crocodylus falconensis'' is an extinct crocodile from Early Pliocene of Venezuela. * † ''Crocodylus palaeindicus'' is an extinct crocodile the Miocene to the Pleistocene of southern Asia. * † ''Crocodylus thorbjarnarsoni'' is an extinct crocodile from Plio-Pleistocene o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodilia
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saltwater Crocodile
The saltwater crocodile (''Crocodylus porosus'') is a crocodilian native to saltwater habitats and brackish wetlands from India's east coast across Southeast Asia and the Sundaic region to northern Australia and Micronesia. It has been listed as Least Concern on the IUCN Red List since 1996. It was hunted for its skin throughout its range up to the 1970s, and is threatened by illegal killing and habitat loss. It is regarded as dangerous to humans. The saltwater crocodile is considered to be the largest living reptile. Males can grow up to a length of , rarely exceeding , and a weight of . Females are much smaller and rarely surpass . It is also called the estuarine crocodile, Indo-Pacific crocodile, marine crocodile, sea crocodile, and informally as the saltie. A large and opportunistic hypercarnivorous apex predator, they ambush most of their prey and then drown or swallow it whole. They are capable of prevailing over almost any animal that enters their territory, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylinae
Crocodylinae is a subfamily of true crocodiles within the family Crocodylidae, and is the sister taxon to Osteolaeminae ( dwarf crocodiles and slender-snouted crocodiles). Taxonomy Crocodylinae was cladistically defined by Christopher Brochu in 1999 as ''Crocodylus niloticus'' (the Nile crocodile) and all crocodylians more closely related to it than to ''Osteolaemus tetraspis'' (the Dwarf crocodile). This is a stem-based definition, and is the sister taxon to Osteolaeminae. Crocodylinae contains the extant genus '' Crocodylus''. It is disputed as to whether is also includes ''Mecistops'' (slender-snouted crocodiles), or the extinct genus Voay. Phylogeny Some morphological studies have recovered ''Mecistops'' as a basal member of Crocodylinae, more closely related to '' Crocodylus'' than to ''Osteolaemus'' and the other members of Osteolaeminae, as shown in the cladogram below. The below cladogram is based on a 2021 study using paleogenomics that extracted DNA from the ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nile Crocodile
The Nile crocodile (''Crocodylus niloticus'') is a large crocodilian native to freshwater habitats in Africa, where it is present in 26 countries. It is widely distributed throughout sub-Saharan Africa, occurring mostly in the central, eastern, and southern regions of the continent, and lives in different types of aquatic environments such as lakes, rivers, swamps, and marshlands. In West Africa, it occurs along with two other crocodilians. Although capable of living in saline environments, this species is rarely found in saltwater, but occasionally inhabits deltas and brackish lakes. The range of this species once stretched northward throughout the Nile, as far north as the Nile Delta. On average, the adult male Nile crocodile is between in length and weighs including stomach stones. However, specimens exceeding in length and weighing up to have been recorded. It is the largest freshwater predator in Africa, and may be considered the second-largest extant reptile in the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False Gharial
The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals. The specific name ''schlegelii'' honors Hermann Schlegel. Taxonomy The scientific name ''Crocodilus (Gavialis) schlegelii'' was proposed by Salomon Müller in 1838 who described a specimen collected in Borneo. In 1846, he proposed to use the name ''Tomistoma schlegelii'', if it needs to be placed in a distinct genus. The genus ''Tomistoma'' potentially also contains several extinct species like ''T. cairense'', ''T. lusitanicum'', ''T. taiwanicus'', and ''T. coppensi''. However, these species may need to be reclassified to different genera as are paraphyletic. The false gharial's snout broadens considerably towards the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialidae
Gavialidae is a family (biology), family of large semiaquatic crocodilians with elongated, narrow snouts. Gavialidae consists of two extant taxon, living species, the gharial (''Gavialis gangeticus'') and the false gharial (''Tomistoma schlegelii''), both occurring in Asia. Many extinct members are known from a broader range, including the recently extinct ''Hanyusuchus''. Gavialids are generally regarded as lacking the jaw strength to capture the large mammalian prey favoured by crocodiles and alligators of similar size so their thin snout is best used to catch fish, however the false gharial has been found to have a Generalist and specialist species, generalist diet with mature adults preying upon larger vertebrates, such as Ungulate, ungulates. Taxonomy The family Gavialidae was proposed by Arthur Adams (zoologist), Arthur Adams in 1854 for reptiles with a very long and slender muzzle, webbed feet and nearly equal teeth. It is currently recognized as a crown group, meaning that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alligatoridae
The family Alligatoridae of crocodylians includes alligators, caimans and their extinct relatives. Phylogeny The superfamily Alligatoroidea includes all crocodilians (fossil and extant) that are more closely related to the American alligator than to either the Nile crocodile or the gharial. This is a stem-based definition for alligators, and is more inclusive than the crown group Alligatoridae. As a crown group, Alligatoridae only includes the last common ancestor of all extant (living) alligators, caimans, and their descendants (living or extinct), whereas Alligatoroidea, as a stem-based group, also includes more basal extinct alligator ancestors that are more closely related to living alligators than to crocodiles or gavialids. When considering only living taxa (neontology), this makes Alligatoroidea and Alligatoridae redundant. The simplified cladogram below shows Alligatoridae's relationships to other extant (living) crocodilians. The below detailed cladogram show ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gharial
The gharial (''Gavialis gangeticus''), also known as gavial or fish-eating crocodile, is a crocodilian in the family Gavialidae and among the longest of all living crocodilians. Mature females are long, and males . Adult males have a distinct boss at the end of the snout, which resembles an earthenware pot known as a ''ghara'', hence the name "gharial". The gharial is well adapted to catching fish because of its long, narrow snout and 110 sharp, interlocking teeth. The gharial probably evolved in the northern Indian subcontinent. Fossil gharial remains were excavated in Pliocene deposits in the Sivalik Hills and the Narmada River valley. It currently inhabits rivers in the plains of the northern part of the Indian subcontinent. It is the most thoroughly aquatic crocodilian, and leaves the water only for basking and building nests on moist sandbanks. Adults mate at the end of the cold season. Females congregate in spring to dig nests, in which they lay 20–95 eggs. They guard t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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