Heikegani - Heikegani

This crab belongs to the family Heikebani, order Decapoda, class Crustacea, phylum Arthropoda. It is found in the Seto Inland Sea, Ariake Sea, the west coast of the Korean Peninsula, and northern China. It lives on a sandy bottom mixed with shells at a depth of 30 to 100 meters. The carapace is about 2 centimeters long and wide, narrow at the front. Because the carapace looks like an angry face, and because they are found in abundance in the Seto Inland Sea, there is a legend that the ghost of the Heike clan, who were defeated in the battle with the Genji at Dannoura, has possessed it. The part that looks like upturned eyes is the anterior gill region, the large nose is the heart region, and the mouth that is closed in a straight line is the rear edge of the carapace. The first two pairs of walking legs are remarkably long and normal in shape, but the last two pairs of legs are biased toward the back, with the tips being hook-shaped and forming pincers together with the front segments. With this, it hides itself by carrying the bivalve shell on its back. The closely related Paradorippe granulata , which is found from Hokkaido to China, is densely covered with fine granules, while the yellow crab Dorippe frascone , which is found widely in the Indian Ocean, has numerous wart-like protrusions on its shell.

[Masamichi Takeda]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

節足動物門甲殻綱十脚(じっきゃく)目ヘイケガニ科に属するカニ。瀬戸内海、有明(ありあけ)海、朝鮮半島西岸、中国北部に分布する。水深30～100メートルの貝殻混じりの砂底にすむ。甲長、甲幅とも2センチメートルほどで、前方が狭い。甲域が怒った人の顔のようにみえ、そのうえ、瀬戸内海に多産するため、壇ノ浦(だんのうら)で源氏との戦いに敗れた平家の亡霊がのりうつったという伝説がある。つり上がった目のようにみえる部分は前鰓域(さいいき)、大きな鼻は心域、一文字に結んだ口は甲の後縁である。前2対の歩脚は著しく長く、正常の形であるが、後2対の脚(あし)は背中側に偏り、先端が鉤(かぎ)づめ状となって前節とともにはさみを形成する。これで二枚貝の殻を背負って身を隠す。近縁のサメハダヘイケガニParadorippe granulataは北海道から中国まで分布し、細かい顆粒(かりゅう)で密に覆われている。また、キメンガニDorippe frasconeはインド洋まで広く分布し、甲面にいぼ状突起が多数ある。

［武田正倫］

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例