Caiman

Caiman
A caiman (also cayman as a variant spelling from Taíno kaiman) is an alligatorid belonging to the subfamily Caimaninae, one of two primary lineages within the Alligatoridae family, the other being alligators. Caimans inhabit Mexico and Central & 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 of the other caiman species is about long.
Caimans are distinguished from alligators, their closest relatives, by a few defining features: a lack of a bony septum between the nostrils, ventral armor composed of overlapping bony scutes formed from two parts united by a suture, and longer and sharper teeth than alligators, plus caimans tend to be more agile and crocodile-like in their movements. The calcium rivets on caiman scales make their hides stiffer.
Several extinct forms are known, including Purussaurus, a giant Miocene genus that grew to and the equally large Mourasuchus, which had a wide duck-like snout.
Behavior
Caimans are predators and, like alligators and crocodiles, their diet largely consists of fish. Caimans also hunt insects, birds, small mammals and reptiles.
Due to their large size and ferocious nature, caimans have few natural predators within their environments. Humans are their main predators, because the animals have been hunted for their meat and skin. Jaguars, anacondas and crocodiles are the only other predators of caimans, although they usually prey on the smaller specimens. During summer or droughts, caimans may dig a burrow and go into a form of summer hibernation called aestivation.
Female caimans build a large nest in which to lay their eggs. The nests can be more than wide. Female caimans lay between 10 and 50 eggs, which hatch within about six weeks. Once they have hatched, the mother caiman takes her young to a shallow pool of water, where they can learn how to hunt and swim.
Phylogeny
Caimaninae is cladistically defined as Caiman crocodylus (the spectacled caiman) and all species closer to it than to Alligator mississippiensis (the American alligator). This is a stem-based definition for caimaninae, and means that it includes more basal extinct caimanine ancestors that are more closely related to living caimans than to alligators.
Below is a cladogram showing the phylogeny of Caimaninae, modified from Hastings et al. (2013).
Taxonomy
Subfamily Caimaninae
Genus †Acresuchus
Genus †Brachychampsa
Genus †Bottosaurus
Genus †Centenariosuchus
Genus †Chinatichampsus
Genus †Protocaiman
Genus †Kuttanacaiman
Genus †Gnatusuchus
Genus †Culebrasuchus
Genus †Eocaiman
Genus †Globidentosuchus
Genus Paleosuchus
P. palpebrosus, Cuvier's dwarf caiman
P. trigonatus, smooth-fronted caiman
Genus †Purussaurus
Genus †Mourasuchus
Genus †Necrosuchus
Genus †Orthogenysuchus
Genus †Tsoabichi
Genus Caiman
C. yacare, yacare caiman
C. crocodilus, spectacled caiman
C. c. crocodilus, spectacled caiman
C. c. apaporiensis, Rio Apaporis caiman
C. c. fuscus, Brown caiman
†C. lutescens
†C. venezuelensis
†C. wannlangstoni
†C. brevirostris
C. latirostris, broad-snouted caiman
Genus Melanosuchus
†M. fisheri
M. niger, black caiman
References
Alligatoridae
Selandian first appearances
Extant Selandian first appearances
mk:Кајмани