Order of mostly large, predatory, semiaquatic reptiles
Crocodilia
Temporal range: Late Cretaceous – Recent 94–0 Ma
PreꞒ
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
Clockwise from top-left: saltwater crocodile (Crocodylus porosus), American alligator (Alligator mississippiensis), and gharial (Gavialis gangeticus)
Scientific classification
Domain:
Eukaryota
Kingdom:
Animalia
Phylum:
Chordata
Class:
Reptilia
Clade:
Archosauria
Clade:
Pseudosuchia
Clade:
Crocodylomorpha
Clade:
Crocodyliformes
Clade:
Eusuchia
Order:
Crocodilia Owen, 1842
Subgroups
Alligatoroidea
Alligatoridae
Longirostres
Gavialoidea
Gavialidae
Crocodyloidea
Crocodylidae
†Mekosuchinae
†?Planocraniidae
†Pristichampsidae
†Prodiplocynodon
†Asiatosuchus
†Brachyuranochampsa
†"Crocodylus" affinis
†"Crocodylus" acer
Crocodylia distribution on land (green) and at sea (blue)
Crocodilia (or Crocodylia, both /krɒkəˈdɪliə/) 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. The order Crocodilia includes the true crocodiles (family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae). Although the term crocodiles (or crocs) is sometimes used to refer to all of these, crocodilians is a less ambiguous vernacular term for members of this group.
Large, solidly built, lizard-like reptiles, crocodilians have long flattened snouts, laterally compressed tails, and eyes, ears, and nostrils at the top of the head. They swim well and can move on land in a "high walk" and a "low walk", while smaller species are even capable of galloping. Their skin is thick and covered in non-overlapping scales. They have conical, peg-like teeth and a powerful bite. They have a four-chambered heart and, somewhat like birds, a unidirectional looping system of airflow within the lungs, but like other living reptiles they are ectotherms.
Crocodilians are found mainly in lowlands in the tropics, but alligators also live in the southeastern United States and the Yangtze River in China. They are largely carnivorous, the various species feeding on animals such as fish, crustaceans, molluscs, birds, and mammals; some species like the Indian gharial are specialised feeders, while others like the saltwater crocodile have generalised diets. Crocodilians are typically solitary and territorial, though cooperative feeding does occur. During breeding, dominant males try to monopolise available females. Females lay eggs in holes or in mounds and, unlike most other reptiles, care for their hatched young.
Some species of crocodilians are known to have attacked humans. The largest number of attacks comes from the Nile crocodile. Humans are the greatest threat to crocodilian populations through activities that include hunting, poaching, and habitat destruction, but farming of crocodilians has greatly reduced unlawful trading in wild skins. Artistic and literary representations of crocodilians have appeared in human cultures around the world since Ancient Egypt. The earliest known mention of the story that crocodiles weep for their victims was in the 9th century; it was later spread by Sir John Mandeville in 1400 and then by William Shakespeare in the late 16th century and early 17th century.
Crocodilia (or Crocodylia, both /krɒkəˈdɪliə/) is an order of mostly large, predatory, semiaquatic reptiles known as crocodilians. They first appeared...
sources. Unsourced material may be challenged and removed. Find sources: "Crocodilia in India" – news · newspapers · books · scholar · JSTOR (November 2014)...
Crocodilia is an order of mostly large, predatory, semiaquatic reptiles, which includes true crocodiles, the alligators and caimans, and the gharial and...
made several short art films. Ridley has written three books for adults: Crocodilia (1988), In the Eyes of Mr. Fury (1989), and Flamingoes in Orbit (1990)...
lumped into the order Crocodilia. However, beginning in the late 1980s, many scientists began restricting the order Crocodilia to the living species and...
epidermal components of the integumentary system in animals of the order Crocodilia. The epidermal scutes of the alligator consists of oblong horny scales...
forward like a wave. On average a tooth is replaced every few months. Crocodilia are the only non-mammalian vertebrates with tooth sockets. Alligators...
reptile in the genus Alligator of the family Alligatoridae of the order Crocodilia. The two extant species are the American alligator (A. mississippiensis)...
the family Alligatoridae. They are the smallest members of the order Crocodilia in the Americas. The genus contains two extant species and a yet unnamed...
This list of largest reptiles takes into consideration both body length and mass of large reptile species, including average ranges and maximum records...
dinosaur clade Theropoda. According to the current consensus, Aves and Crocodilia are the sole living members of an unranked clade, the Archosauria. Simplified...
Extinct in the wild (EW): 2 species Critically endangered (CR): 196 species Endangered (EN): 382 species Vulnerable (VU): 411 species Near threatened...
There are around 170 species of reptiles living in Pakistan. There are only two species found in Pakistan. Family Crocodylidae (crocodiles) - 1 species...
This is a list of reptiles in Madagascar. Total number of species = 406 Acrantophis madagascariensis (Duméril & Bibron, 1844) Acrantophis dumerili (Jan...
of the four reptile orders are represented: Testudines, Squamata and Crocodilia. The only missing extant order is Sphenodontia, containing the tuataras...
sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the...
Museum (Natural History). Part I. Containing the Orders Ornithosauria, Crocodilia, Dinosauria, Squamata, Rhynchocephalia, and Proterosauria. British Museum...
total-group perspective, the Crocodylomorpha would become synonymous with the Crocodilia, and the Avemetatarsalia would become synonymous with the birds, and the...
This is a list of reptiles of Sri Lanka. The reptilian diversity in Sri Lanka is higher than the diversity of other vertebrates such as mammals and fish...
Thoracosaurus †Planocraniidae Boverisuchus Duerosuchus Planocrania Crocodilia see Crocodilia for extant taxa, and Extinct Crocodilia for extinct ones...
The Ellisdale Fossil Site is located near Ellisdale in the valley of the Crosswicks Creek, in Monmouth County, New Jersey, United States. The site has...
Extinct in the wild (EW): 2 species Critically endangered (CR): 196 species Endangered (EN): 382 species Vulnerable (VU): 411 species Near threatened...
as marine crocodiles or sea crocodiles, though they are not members of Crocodilia and records from Thailand and China suggest that some members lived in...
development. Living reptiles comprise four orders: Testudines (turtles), Crocodilia (crocodilians), Squamata (lizards and snakes), and Rhynchocephalia (the...
This is a list of reptile species found in Sumatra, Indonesia. Crocodylus porosus Tomistoma schlegelii Batagur affinis Batagur borneoensis Cuora amboinensis...
between the sprawling position of basal tetrapods (still observed in modern Crocodilia) and the more upright posture present in current mammals. Thrinaxodon...
Stellung der Gavialiden im System der Crocodilia" [On the position of the Gavialids in the system of the Crocodilia]. Revue Suisse de Zoologie. 38 (3):...
This List of reptiles of Nepal presents reptile species recorded in Nepal. Family: Crocodilidae Mugger crocodile (Crocodylus palustris) Family: Gavialiidae...
Extinct in the wild (EW): 2 species Critically endangered (CR): 196 species Endangered (EN): 382 species Vulnerable (VU): 411 species Near threatened...