What's the difference between sunray and tortoise?

Shanrui is very similar to China soft-shelled turtle in appearance, also known as "turtle". It is round, but slightly fat, with a body length of 30-40 cm, a width of 23 cm and a weight of 20 kg. The head is large, conical, dark black or dark green. The kiss protrudes forward to form a tubular kiss. The nostrils open at the end of the snout and are often exposed to water to breathe. The eyes are on the side of the head. The skin is soft and rough, and there is no horny shield like a turtle. The neck is long, and there are a group of fleshy hump-shaped large grains on both sides of the base of the neck and the front edge of the carapace, and there is a row of thick convex grains on the front edge of the dorsal plate, which can be distinguished from the soft-shelled turtle. The body is stout, the back and abdomen are wrapped by bone plates, and the left and right are connected to form a special "armor", with a dark green back and black spots on it; The abdomen of the body is white and covered with black spots. There is a wide and thick skin around the nails, just like a short skirt, so it is called a skirt. The limbs are flat, the trailing edge is thin, paddle-shaped, and it is also dark black or dark green. There are developed webbed toes with three claws, which are suitable for swimming and diving in the water. The male's tail is narrow and long, which can exceed the skirt, while the female's tail is wide and short, which can tell its gender.