First of all, we can judge by looking at the shape: Male: The belly is concave, the body is small, the shell is black, the body is long and thin, and the tail is long and stalked; Female: The belly is flat, the body is larger, and the shell is thin. Brown-yellow, with prominent longitudinal edges, short and thick trunk, short and thick tail.

Secondly, observe the condition of the plastron of the ptar Obvious concave, flat plastron in females.