Urechis unicinctus
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Urechis unicinctus as a food in Korea |
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| Scientific name | ||||||||||||
| Urechis unicinctus | ||||||||||||
| ( from Drasche , 1881) |
Urechis unicinctus is the name of a large sand-burrowing species of hedgehog worms (Echiura) from the Urechidae familythat is found in the Pacific Ocean on the coasts of China , Korea and Japan .
features
The cylindrical, sausage-shaped, yellowish-brown trunk of Urechis unicinctus , covered with many small papillae, has a wrinkled skin and is about 10 cm to 30 cm long. At the front there are two hooks on the belly side, around the anus at the end of the trunk a conspicuous ring of 10 to 13 bristles. At the front end near the mouth there is a spoon-shaped, short proboscis . Urechis unicinctus has 2 pairs of nephridia .
Distribution and occurrence
Urechis unicinctus is found in the western Pacific Ocean from the mouth of the Amur to Japan and Korea as well as in Chinese coastal waters at shallow sea depths, buried in the sandy subsoil.
Way of life
Urechis unicinctus digs a U-shaped living cave. Through peristaltic movements of the body, it creates a flow of water to supply oxygen and fine food particles, which are filtered out of the water using a network of mucus. If there are enough particles on the slime web, it will be swallowed.
Life cycle
Males and females are the same size in Urechis unicinctus and can be found in larger groups to mate. The gametes are released to the outside via the nephridia, so that fertilization takes place in the open sea water. The floating Trochophora larvae live for several weeks pelagial before they sink down and ground-dwelling worms metamorphose .
Importance to humans
Urechis unicinctus is eaten in China, Korea, and Japan. Due to its resemblance to a human penis , it is also known in China as the "penis fish" (陰莖 魚).
literature
- Richard Freiherr von Drasche (1881): About a new species of Echiurus from Japan together with remarks about Thalassema erythrogrammon S. Leuckart from the island of Bourbon. Negotiations of the Imperial-Royal Zoological-Botanical Society in Vienna 30, pp. 621–628.
- H. Sato (1939): Studies on the Echiuroidea, Sipunculoidea and Priapuloidea of Japan. Science Reports of the Tôhoku University, Ser. 4 (Biology), Volume 14, pp. 339-460, here p. 350.
- WK Fisher, GE MacGinitie (1928): The natural history of an echiuroid worm (Urechis). Ann. Mag. Natural History (10) 1, pp. 204-213.
