Oval squid - Aoriika (English spelling)

A squid of the family Squididae of the class Cephalopoda of the phylum Mollusca. It is widely distributed throughout Japan from Hokkaido southward, and in temperate and tropical regions of the Indian Ocean and the Western Pacific Ocean. Its mantle is 45 cm long and 13 cm wide. Its mantle is cone-shaped with a widened center, and its fins are wide and extend the entire length of both sides of the mantle. This appearance has earned it the local names of Bashoika and Kutsuika. Its arms are relatively short, less than half the length of the mantle, and it has two rows of suckers on the arms, but four rows on the palms of its tentacles. The tip of the fourth arm on the left is the hectocotyl, and its suckers have changed into a nipple-like fleshy beak. When alive, it has many short white horizontal stripes on its dorsal side, which are particularly noticeable in males. It has a thin, willow-leaf-shaped carapace in the center of its dorsal side, wrapped in the mantle. This species does not form large schools, but comes to the coast in May and June to spawn on seaweed or sunken logs. The local name "moika" ("moi squid") comes from this characteristic. The eggs are about 10 millimeters in diameter, with 2-8 of them contained in an agar-based sheath, and the hatched baby squid have a mantle length of 6 millimeters. They are mainly caught in fixed coastal nets, but can also be caught with unique baits (called egi in the western Kagoshima region). The meat is soft and sweet, and is of high quality, and is used as sashimi, while the dried product is called mizusurume (from the local name mizuika) or mozurume, and is expensive.

[Takashi Okutani]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

軟体動物門頭足綱ジンドウイカ科のイカ。北海道以南の日本各地、インド洋や西太平洋の温帯、熱帯域に広く分布する。外套(がいとう)長45センチメートル、幅13センチメートルぐらい。外套膜は中央の広がった円錐(えんすい)形、ひれは外套膜の両側全長に及び、広い。このようすからバショウイカ、クツイカという地方名がある。腕は比較的短く、外套長の半分以下で、吸盤は腕に2列並ぶが、触腕掌部には4列並ぶ。左第4腕の先端は交接腕で、その吸盤は乳頭状肉嘴(にくし)に変わっている。生時は背側に多数の短く白い横縞(よこじま)があり、雄ではとくに顕著。外套に包まれて背側中央に薄質で柳葉形の軟甲がある。本種はあまり大群をつくることなく5～6月には沿岸にきて海藻や沈木に産卵。モイカという地方名は、この性質に由来する。卵は直径10ミリメートルぐらいで2～8個が寒天質の鞘(さや)に収まっていて、孵化(ふか)した子イカは外套長6ミリメートルもある。主として沿岸の定置網などに入り、また独特の擬餌鉤(ぎじばり)（西鹿児島地方では餌木(えぎ)という）でも釣られる。肉は柔らかく甘味があり上等で刺身にされ、乾製品は、みずするめ（ミズイカという地方名から）とか、もずるめといい、高価である。

［奥谷喬司］

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