Caiman

Caimans Temporal range: Paleocene—Present, 60–0 Ma PreЄ Є O S D C P T J K Pg N
Yacare caiman, Caiman yacare
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	Crocodylomorpha
Order:	Crocodilia
Family:	Alligatoridae
Subfamily:	Caimaninae Brochu, 1999
Type species
Caiman latirostris Daudincrrefwad, 1825
Genera and Species
See below

A caimán is an alligatorid crocodilian belonging to the subfamily Caimaninae, one of two primary lineages within Alligatoridae, the other being alligators.

Description

Caimans inhabit Central and South America. They are relatively mid-small sized crocodilians, with the smallest being Cuvier's dwarf caiman (Paleosuchus palpebrosus), which grows to 1 m (3 ft) long, and the largest being the black caiman (Melanosuchus niger), which can grow to  5 m (15 ft) or more. Caimans are distinguished from alligators, their closest (and more widely-known) 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 relatively longer, more slender teeth than those that alligators possess. Several extinct forms are known, including Purussaurus, a giant Miocene genus that grew to 12 m (39 ft) and the equally large Mourasuchus, which had a wide duck-like snout.^[1]

Taxonomy

Spectacled caiman (Caiman crocodilus)

Broad-snouted caiman (Caiman latirostris)

Yacare caiman (Caiman yacare)

Black caiman (Melanosuchus niger)

Cuvier's dwarf caiman (Paleosuchus palpebrosus)

Smooth-fronted caiman (Paleosuchus trigonatus)

• Subfamily Caimaninae
  • Genus †Centenariosuchus
  • 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
  • Clade Jacarea
    • Genus Caiman
      • C. yacare, yacare caiman
      • C. crocodilus, spectacled caiman
        • C. c. apaporiensis, Rio Apaporis caiman
        • C. c. fuscus, brown caiman
      • †C. lutescens
      • †C. venezuelensis
      • C. latirostris, broad-snouted caiman
    • Genus Melanosuchus
      • †M. fisheri
      • M. niger, black caiman

Phylogeny

Below is a cladogram modified from Brochu (2011).^[2]

Alligatoridae	Alligatorinae  Caimaninae  †Eocaiman cavernensis †Necrosuchus ionensis †Tsoabichi greenriverensis Paleosuchus palpebrosus Paleosuchus trigonatus †Mourasuchus †Orthogenysuchus olseni †Purussaurus mirandai †Purussaurus neivensis  Jacarea  Caiman crocodilus Caiman yacare Caiman latirostris UCMP 39978 (referred to Caiman lutescens) †Melanosuchus fisheri Melanosuchus niger

Below is a cladogram modified from Hastings et al. (2013).^[3]

†Stangerochampsa mccabei †Brachychampsa montana †Brachychampsa sealeyi  Alligatoridae  Alligatorinae  Caimaninae  †Culebrasuchus mesoamericanus †Eocaiman cavernensis †Tsoabichi greenriverensis Paleosuchus palpebrosus Paleosuchus trigonatus †Centenariosuchus gilmorei †Purussaurus neivensis †Mourasuchus †Orthogenysuchus olseni Caiman crocodilus Caiman yacare Caiman latirostris †Caiman lutescens †Melanosuchus fisheri Melanosuchus niger

References

1. Brochu, C. A. (1999). "Phylogenetics, Taxonomy, and Historical Biogeography of Alligatoroidea". Society of Vertebrate Paleontology Memoir 6: 9–100. doi:10.2307/3889340. JSTOR 3889340.
2. Brochu, C. A. (2011). "Phylogenetic relationships of Necrosuchus ionensis Simpson, 1937 and the early history of caimanines". Zoological Journal of the Linnean Society 163: S228–S256. doi:10.1111/j.1096-3642.2011.00716.x.
3. Hastings, A. K.; Bloch, J. I.; Jaramillo, C. A.; Rincon, A. F.; MacFadden, B. J. (2013). "Systematics and biogeography of crocodylians from the Miocene of Panama". Journal of Vertebrate Paleontology 33 (2): 239. doi:10.1080/02724634.2012.713814.