The family Alligatoridae of crocodylians includes alligators, caimans and their extinct relatives.
Gavialinae is a subfamily of large semiaquatic crocodilian reptiles, resembling crocodiles, but with much thinner snouts. Gavialinae is one of the two major subfamilies within the family Gavialidae - the other being the subfamily Tomistominae, which contains the false gharial and extinct relatives.
Caiman is a genus of caimans within the alligatorid subfamily Caimaninae. They inhabit Central and South America. They are relatively small sized crocodilians, with all species reaching lengths of only a couple of meters and weighing 6 to 40 kg on average.
Tomistoma is a genus of gavialid crocodilians. They are noted for their long narrow snouts used to catch fish, similar to the gharial. Tomistoma contains one extant (living) member, the false gharial, as well as potentially several extinct species: T. cairense, T. lusitanicum and T. coppensi. Previously assigned extinct species known from fossils are reclassified as different genera such as Eogavialis, Toyotamaphimeia and Sutekhsuchus.
Purussaurus is an extinct genus of giant caiman that lived in South America during the Miocene epoch, from the Friasian to the Huayquerian in the SALMA classification. It is known from skull material found in the Brazilian and Peruvian Amazon, Colombian Villavieja Formation, Panamanian Culebra Formation, Urumaco and Socorro Formations of northern Venezuela.
Paleosuchus is a South American genus of reptiles in the subfamily Caimaninae of the family Alligatoridae. They are the smallest members of the order Crocodilia in the Americas.
Mourasuchus is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck-like, being broad, flat, and very elongate, superficially resembling Stomatosuchus from the Late Cretaceous.
A caiman is an alligatorid belonging to the subfamily Caimaninae, one of two primary lineages within the Alligatoridae family, the other being alligators. Caimans are native to Central and South America and inhabit marshes, swamps, lakes, and mangrove rivers. They have scaly skin and live a fairly nocturnal existence. They are relatively small-sized crocodilians with an average maximum weight of 6 to 40 kg depending on species, with the exception of the black caiman, which can grow more than 4 m (13 ft) in length and weigh in excess of 450 kg. 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, which grows to 1.2 to 1.5 m long. There are six different species of caiman found throughout the watery jungle habitats of Central and Southern America. The average length for most of the other caiman species is about 2 to 2.5 m long.
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.
Eocaiman is an extinct genus of caiman containing species living from the Early Paleocene to Miocene in what is now Argentina, Itaboraí Formation of Brazil and Colombia. Eocaiman contains three described species: E. cavernensis, E. palaeocenicus, and E. itaboraiensis, and is typically recovered as one of the more basal members of Caimaninae. Notocaiman was synonymized with Eocaiman paleocenicus in 2022.
Stangerochampsa is an extinct genus of alligatorid, possibly an alligatorine or a stem-caiman, from the Late Cretaceous of Alberta. It is based on RTMP.86.61.1, a skull, partial lower jaws, and partial postcranial skeleton discovered in the late Campanian–early Maastrichtian-age Horseshoe Canyon Formation. Stangerochampsa was described in 1996 by Wu and colleagues. The type species is S. mccabei. The generic name honors the Stanger family, the owners of the ranch where the specimen was found, and the species name honors James Ross McCabe, who discovered, collected, and prepared it. Stangerochampsa is described as "small to medium–sized"; the type skull is 20.0 centimetres (7.9 in) long from the tip of the snout to the occipital condyle, and is 13.0 centimetres (5.1 in) wide at its greatest, while the thigh bone is 14.2 centimetres (5.6 in) long. It had heterodont dentition, with large crushing teeth at the rear of the jaws.
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 and all forms more closely related to it than to Diplocynodon. The group's fossil range extends back into the Campanian stage of 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.
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.
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.
Brevirostres is a paraphyletic group of crocodilians that included alligatoroids and crocodyloids. Brevirostres are crocodilians with small snouts, and are distinguished from the long-snouted gharials. It is defined phylogenetically as the last common ancestor of Alligator mississippiensis and Crocodylus niloticus and all of its descendants. This classification was based on morphological studies primarily focused on analyzing skeletal traits of living and extinct fossil species, and placed the gharials outside the group due to their unique skull structure, and can be shown in the simplified cladogram below:
Jacarea is a clade of caimans within the subfamily Caimaninae. Jacarea was first named by Norell in 1988 to include the extant species within the genera Caiman and Melanosuchus, while excluding the dwarf caiman genus Paleosuchus. In 1999, Brochu formally cladistically defined Jacarea as the last common ancestor of Caiman latirosris, Caiman crocodilus, Caiman yacare, Melanosuchus niger, and all its descendants. Molecular DNA phylogenetic studies recover Paleosuchus as outside of Jacarea, although morphological studies are inconsistent.
Globidentosuchus is an extinct genus of basal caimanine crocodylian known from the late Middle to Late Miocene of the Middle and the Upper Members of the Urumaco Formation at Urumaco, Venezuela. Its skull was very short and robust, with large units of spherical teeth used to break the shells of molluscs as part of its durophagus diet. It is thought to be one of the most basal Caimanines, even sharing some traits with alligatorids.
Caiman wannlangstoni is an extinct species of caiman that lived in what is now the Amazon Basin and surrounding areas during the Middle and Late Miocene. Fossils of C. wannlangstoni have been found in the Pebas Formation near Iquitos in Peru and include partial skulls and isolated skull bones. Other fossils were uncovered from the Urumaco Formation in Venezuela and the Laventan Honda Group of Colombia. The species was first described in 2015. Features that in combination distinguish C. wannlangstoni from other caimans include a deep snout, a wavy upper jaw margin, a large and upward-directed narial opening, and blunt teeth at the back of the jaws. Based on the sizes of the skulls, its estimated body length is about 211 to 227 centimetres.
Caiman brevirostris is an extinct species of caiman that lived during the Late Miocene, around 11.6 million years ago, to the end of the Miocene 5.3 million years ago in Acre and Amazonas, Brazil as well as Urumaco, Venezuela. Several specimens have been referred to the species, but only 3 of them are confidently placed in the species. C. brevirostris was originally named in 1987 on the basis of a single, incomplete rostrum with an associated mandibular ramus that had been found in Acre, Brazil. C. brevirostris is very distinct among Caiman species and caimaninae overall in that it preserves a characteristically short and robust skull that bears blunt posterior teeth that were built to break down harder foods. This was an adaption for durophagy, likely to crush shells of mollusks and clams which were common in the wetlands that C. brevirostris resided in.
Acresuchus is an extinct monospecific genus of medium-sized caiman from the Late Miocene of western Brazil and Venezuela. The genus contains a single species, Acresuchus pachytemporalis. Acresuchus is a close relative of the giant caiman Purussaurus.
