Itome - Itome

A marine animal belonging to the order Polychaeta, phylum Annelida, and family Nereididae. Also known as Negkai, Akaguda, etc. It is found throughout Japan, from the muddy areas of inland bays to places quite upstream in rivers. The body is slender and long, 20 to 30 centimeters, with about 300 segments. The front part of the body is greenish brown and the middle part is red. Most species of Nereididae have many small jawlets on their snouts, but Itome has several fleshy protrusions like bumps. It has four eyes, which are relatively large. In autumn, males and females mature and fill the front part of their bodies with reproductive material. Then, a few days after the new moon in October to December, they all emerge from the mud at the same time, rise to the surface of the water, swim in groups, lay eggs, and are fertilized. In this state, they are called Bachi, Ukiko, Hiru, Eba, or Japanese Parolo, and morphologically, their eyes are large and protruding, and their rear warty legs are wide, which makes them more convenient for swimming. It is used as bait for fishing for mullet, flounder, sea bass, black porgy, goby, and horse mackerel.

[Minoru Imajima]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

環形動物門多毛綱遊在目ゴカイ科に属する海産動物。別名ゴカイ、アカグダなど。日本各地に分布し、内湾の泥地からかなり川をさかのぼった場所まで分布する。虫体は細長く20～30センチメートル、環節数は約300個。体の前部は緑褐色で中央部は紅色。ゴカイ科の大部分の種類は、吻(ふん)に多くの小顎片(しょうがくへん)をもっているが、イトメにはいくつかのこぶのような肉質突起がある。目は4個あって比較的大きい。秋になると雌雄が成熟して、体の前部に生殖物を充満させる。そして10～12月の新月の数日後に一斉に泥中から抜け出し、水面に浮上して群泳し、産卵、受精する。この状態のものをバチ、ウキコ、ヒル、エバ、または日本パロロとよび、形態的には目が大きく突出し、後部のいぼ足が幅広くなって泳ぐのに便利になる。ボラ、キス、スズキ、クロダイ、ハゼ、アジ釣りなどの餌(えさ)にされている。

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