The main difference between turtles and turtles is the shell, and the shell of turtles has obvious lines.

The turtle (AmydaSincnsis). Commonly known as soft-shelled turtle, water fish, tuanyu and tortoise, they are oviparous reptiles and live amphibious lives.

Turtles are divided into head, neck, trunk, tail and limbs: the special morphological structure that is significantly different from other reptiles is that it has a turtle shell, and the wide and short body is contained in the turtle shell. The tortoise shell consists of arched carapace and flat carapace: the carapace extends at the side of the body and is connected with the carapace by bone seams or ligaments. This extended part is called nail bridge. The head, limbs and tail extend from the edge of the turtle shell and can generally be retracted into the shell (except for the flat-breasted turtle). The carapace and carapace are composed of two layers: the inner layer is composed of several bone plates and the outer layer is composed of several horny shields. The leatherback family has no horny shield at all, indicating that it is covered with leathery skin and its bone plate has degenerated into many small bone pieces. Turtles have no teeth on the upper and lower jaws, and their jaws are covered with horny sheaths, called beaks. Turtles have a muscular tongue and cannot stick out. There are eyelids and transient membranes, and the pupils are round. Hearing is not keen, touch and smell are developed, and lungs breathe. The anal orifice is round or longitudinal, with a single connector. The shell is slightly flat, and the dorsal abdominal nail is fixed and immobile. The dorsal nail is 10-113cm long and16cm wide, with three longitudinal ridges. There are yellow linear stripes on the side of the head and neck, the limbs are slightly flat, there are full webbed fingers and toes, and there are claws at the ends of the toes except the fifth hind limb.