Nile crocodileThe 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 in sub-Saharan Africa, occurring mostly in the eastern, southern, and central 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.
Morelet's crocodileMorelet's crocodile (Crocodylus moreletii), also known as the Mexican crocodile or Belize crocodile, is a modest-sized crocodilian found only in fresh waters of the Atlantic regions of Mexico, Belize and Guatemala. It usually grows to about in length. It is a Least Concern species. The species has a fossil record in Guatemala. Morelet's crocodile was first described in 1850 in Mexico by the French naturalist Pierre Marie Arthur Morelet. The species was subsequently named after him.
Saltwater crocodileThe saltwater crocodile (Crocodylus porosus) is a crocodilian native to saltwater habitats, brackish wetlands and freshwater rivers 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 the largest living reptile.
CrocodiliaCrocodilia (or Crocodylia, both krQk@'dIli@) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 94 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.
CrocodileCrocodiles (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.
American alligatorThe 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 the second largest member of the family Alligatoridae, after the black caiman.
Dwarf crocodileThe dwarf crocodile (Osteolaemus tetraspis), also known as the African dwarf crocodile, broad-snouted crocodile (a name more often used for the Asian mugger crocodile) or bony crocodile, is an African crocodile that is also the smallest extant (living) species of crocodile. Dwarf crocodiles attain a medium adult length of , though the maximum recorded length for this species is . Adult specimens typically weigh between , with the largest females weighing up to and the largest males weighing .
OsteolaeminaeOsteolaeminae 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. 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.
