On June 7th, Ant Ocean replied: Guess what the marine animals are called "before the sand"?

The official name of Sha Qianli is cake sea urchin, which is an aquatic wild animal in the ocean and belongs to the class of sea urchins. It is different from the spherical sea urchin, and its shell is obvious on both sides, with five petal-shaped areas arranged on it, which is very similar to the shape of a coin.

Cake sea urchins are widely distributed in shallow seas all over the world, making holes in sand and feeding on organic particles in inlets. Other echinoderms and shellfish are their natural enemies. Some cake sea urchins are coin-shaped and have thin edges, which are called sand money. The word sand money sometimes refers to all cake sea urchins.

Morphological characteristics of biscuit sea urchin

The shell of biscuit sea urchin is relatively flat, the edge is slightly thick, the center of the mouth surface is slightly convex, and the body is slightly round and pentagonal; There are five reproductive holes in the top system, and the water holes of the sieve plate are arranged in an irregular curve groove shape.

The foramen of the tube foot is arranged in a well-developed petal structure, accounting for more than 4/5 of the oral surface. The mouth is located in the center of the ventral surface, and there is no petal pattern. The surface of the thorn on the mouth surface is covered with hairy cilia, which is sticky and can slowly move the food caught by the tube foot into the mouth.