Crocodylia (or "crocodylians") is an order of large reptiles that scientists believe branched off from class Reptilia about 220 million years ago. Orders  Crocodylia - Crocodilians  Rhynchocephalia - Tuataras  Squamata   Suborder Sauria - Lizards   Suborder Serpentes - Snakes Testudines - Turtles Superorder Dinosauria  Saurischia  Ornithischia The reptiles are a group of vertebrate animals. ...

• Order CROCODYLIA
  • Suborder: Eusuchia
  • Family: Crocodylidae
    • Subfamily: Crocodylinae
      • American Crocodile Crocodylus acutus
      • Slender-snouted Crocodile Crocodylus cataphractus
      • Orinoco Crocodile Crocodylus intermedius
      • Australian Freshwater Crocodile Crocodylus johnstoni
      • Philippine Crocodile Crocodylus mindorensis
      • Morelet's Crocodile Crocodylus moreletii
      • Nile Crocodile Crocodylus niloticus
      • New Guinea Crocodile Crocodylus novaeguineae
      • Mugger/Marsh Crocodile Crocodylus palustris
      • Estuarine/Saltwater Crocodile Crocodylus porosus
      • Cuban Crocodile Crocodylus rhombifer
      • Siamese Crocodile Crocodylus siamensis
      • Dwarf Crocodile Osteolaemus tetraspis
      • False Gharial/Gavial Tomistoma schlegelii
    • Subfamily: Alligatoridae (alligators and caimans)
      • Genus: Alligator
        • American Alligator Alligator mississippiensis
        • Chinese Alligator Alligator sinensis
      • Genus: Caiman
        • Common Caiman Caiman crocodilus
          • Bespectacled Caiman Caiman crocodilus crocodilus
          • Brown Caiman Caiman crocodilus fuscus
          • Rio Apaporis Caiman Caiman crocodilus apaporiensis
          • Yacare Caiman Caiman crocodilus yacare
        • Broad-snouted Caiman Caiman latirostros
        • Cuvier's Smooth-fronted Caiman Paleosuchus palpebrosus
        • Scheider's Smooth-fronted Caiman Paleosuchus trigonuatus
        • Black Caiman Melanosuchus niger
    • Subfamily: Gavialinae (Gavial)
      • Gharial Gavialis gangeticus

Genera Crocodylus Osteolaemus Tomistoma A crocodile can be any of the 14 species of large, water-loving reptiles in the family Crocodylidae (sometimes classified instead as the subfamily Crocodylinae). ... Genera Crocodylus Osteolaemus Tomistoma A crocodile can be any of the 14 species of large, water-loving reptiles in the family Crocodylidae (sometimes classified instead as the subfamily Crocodylinae). ... Binomial name Crocodylus acutus (Cuvier, 1807) The American Crocodile is the only New World crocodile and the top predator in its range. ... Binomial name Crocodylus niloticus (Laurenti, 1768) The Nile crocodile is the largest African crocodile and the top predator in its range, which covers most of Africa south of the Sahara, and the islands of Madagascar and Comoros. ... Binomial name Crocodylus rhombifer Cuvier, 1807 The Cuban crocodile (Crocodylus rhombifer) is a small species (8 feet average length) native only to Cubas Zapata Swamp, and highly endangered, though it formerly ranged throughout the Caribbean, possibly even into Florida. ... The Siamese Crocodile is a freshwater crocodile living in Thailand, Indonesia, Borneo, Laos, Malaysia, Myanmar, Thailand, and Vietnam. ... Genera Alligator Caiman Melanosuchus Paleosuchus Alligators and caimans are reptiles closely related to the crocodiles and forming the family Alligatoridae (sometimes regarded instead as the subfamily Alligatorinae). ... Species Alligator mississippiensis Alligator sinensis Alligator is a genus of the Alligatoridae family of crocodile-like reptiles. ... Binomial name Alligator mississippiensis (Daudin, 1801) American Alligator range map The American Alligator (Alligator mississippiensis) is a member of the one of the three families of crocodile-like reptiles, whose members are living fossils from the Age of Reptiles, having survived on earth for 200 million years. ... The Chinese Alligator (Alligator sinesis) is a small relative of the well-known American Alligator. ... Genera Alligator Caiman Melanosuchus Paleosuchus Alligators and caimans are reptiles closely related to the crocodiles and forming the family Alligatoridae (sometimes regarded instead as the subfamily Alligatorinae). ... Binomial name Melanosuchus niger Spix, 1825 The Black Caiman (Melanosuchus niger) is an endangered species, related to alligators. ... Binomial name Gavialis gangeticus (Gmelin, 1789) // Taxonomy The Gharial (Gavialis gangeticus) is the only surviving member of the family Gavialidae, a long-established group of crocodile-like reptiles with long, narrow jaws. ...

Extinct suborders and families

Suborder: Eusuchia (one family living, see above)

• Family: Stomatosuchidae
• Family: Hylaeochampsidae
• Family: Bernissartiidae
• Family: Stomatosuchidae
• Family: Crocodylidae

Suborder: Protosuchia

• Family: Protosuchidae
• Family: Sphenosuchidae

Suborder: Mesosuchia

• Family: Atoposauridae
• Family: Goniopholidae
• Family: Paralligatoridae
• Family: Notosuchidae
• Family: Libycosuchidae
• Family: Sphagesauridae
• Family: Hsisosuchidae
• Family: Teleosauridae
• Family: Pholidosauridae
• Family: Congosauridae

Suborder: Sebecosuchia

• Family: Baurusuchidae
• Family: Sebecidae

Suborder: Thalattosuchia

• Family: Metriorhynchidae

Systems

Circulatory

Like mammals and unlike other reptiles, crocodiles have a four-chambered heart; however, unlike mammals, oxygenated and deoxygenated blood can be mixed when the foramen of Panazzi is open, which bridges both ventricles in the heart. This opening is typically only open during diving, in order to shunt blood away from the lungs.

External links

• http://www.il-st-acad-sci.org/kingdom/rept007.html
• http://www.il-st-acad-sci.org/kingdom/rept007a.html
• Florida's Museum of Natural History's Crocodilians Natural History & Conservation site
• International Crocodile Rescue