Sea cucumber is a marine echinoderm that lives from the seaside to 8000 meters. It has a history of more than 600 million years. Sea cucumber feeds on algae and plankton on the seabed.
Sea cucumbers are covered with stings, which are widely distributed in the oceans of the world. There are many kinds of sea cucumbers along the coast of South China Sea, about 20 kinds of which are edible. Sea cucumbers are as famous as ginseng, bird's nest and shark's fin, and are one of the eight treasures in the world.
Appearance characteristics of sea cucumber
The appetite of sea cucumber is at the front end, mostly on the ventral side. The anus is at the back end, mostly on the back. There are generally wart feet on the back and tube feet on the abdomen. The endoskeleton degenerates into tiny bone fragments. Many species have five rows of tube feet from mouth to anus. Anal foramen is also responsible for breathing and discharging waste. The sea cucumber body is cylindrical, with a length of10 ~ 20 cm, and the extra-large body can reach 30 cm, with dark color and many stings.
Tentacle wheel,17 ~ 30, generally 20. Touch and hand jars are well developed. Sea cucumber thrived on the earth earlier than primitive fish, and began to exist in Precambrian about 600 million years ago. It is the earliest living biological species and is known as the living marine fossil.