Search results
Results From The WOW.Com Content Network
Around the edge of the shell are 12 pairs of marginal scutes. All these scutes are aligned so that for the most part the sutures between the bones are in the middle of the scutes above. At the anterior of the shell there may be a cervical scute (sometimes incorrectly called a nuchal scute) however the presence or absence of this scute is highly ...
Dermal scutes are also found in the feet of birds and tails of some mammals, and are believed to be the primitive form of dermal armour in reptiles. The term is also used to describe the heavy armour of the armadillo and the extinct Glyptodon , and is occasionally used as an alternative to scales in describing snakes or certain fishes, such as ...
Scutes on a crocodile. Reptile skin is covered with scutes or scales which, along with many other characteristics, distinguish reptiles from animals of other classes. They are made of alpha and beta-keratin and are formed from the epidermis (contrary to fish, in which the scales are formed from the dermis).
The "central scutes" extend over the dorsal mid line of the carapace from head to tail, with the "costal scutes" running along each side of the central scutes. The "marginal scutes" run along the outer sides of the shell, and the "nuchal scutes" are found in the area directly behind the turtle's head.
The scales and scutes of birds were thought to be homologous to those of reptiles, [4] but are now agreed to have evolved independently, being degenerate feathers. [ 5 ] [ 6 ] Carcharodontosaurid theropod dinosaur Concavenator , is known to have possessed these feather-derived tarsal scutes.
Typically, 11 or 12 pairs of marginal scutes rim the carapace. [8] Five vertebral scutes run down the carapace's midline, while five pairs of costal scutes border them. [21] The nuchal scute is located at the base of the head. [21] The carapace connects to the plastron by three pairs of inframarginal scutes forming the bridge of the shell. [21]
The dorsal surface of the turtle's head has a single pair of prefrontal scales. Its carapace is composed of five central scutes flanked by four pairs of lateral scutes. Underneath, the green turtle has four pairs of inframarginal scutes covering the area between the turtle's plastron and its shell.
Snake scales occur in variety of shapes. They may be cycloid as in family Typhlopidae, [11] long and pointed with pointed tips, as in the case of the green vine snake Ahaetulla nasuta, [12] broad and leaf-like, as in the case of green pit vipers Trimeresurus spp. [12] or as broad as they are long, for example, as in rat snake Ptyas mucosus. [12]