Turtles are reptiles of the order Testudines. They are characterized by a special bony or cartilaginous shell developed from their ribs that acts as a shield. Turtles are one of the oldest reptile groups, more ancient than snakes or crocodilians. Of the 360 known extant (living) species, some are highly endangered.

Turtles are ectotherms—commonly called cold-blooded—meaning that their internal temperature varies according to the ambient environment. However, because of their high metabolic rate, leatherback sea turtles have a body temperature that is noticeably higher than that of the surrounding water. Turtles are classified as amniotes, along with other reptiles, birds, and mammals. Like other amniotes, turtles breathe air and do not lay eggs underwater, although many species live in or around water.

A group of turtles is known as a bale.

https://en.wikipedia.org/wiki/Turtle