Turtle Shell

Turtle shell

The turtle shell is a shield for turtles, completely enclosing all the turtle's vital organs and in some cases even the head. It comprises an upper part, the carapace, and lower part, the plastron, connected by a bony bridge. It is constructed of modified bony elements such as the ribs, parts of the pelvis, and other bones found in most reptiles. The bone of the shell consists of both skeletal and dermal bone, showing that the complete enclosure of the shell likely evolved by including dermal armor into the rib cage.

Turtle

Turtles are reptiles characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira and Cryptodira, which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean. Like other amniotes they breathe air and do not lay eggs underwater, although many species live in or around water.

turtle-shell

Noun

1. Alternative form of turtleshell.