Coral crab - Sangogani (English spelling)

Japanese: サンゴガニ - さんごがに（英語表記）coral crab

This crab belongs to the order Decapoda of the class Crustacea of the phylum Arthropoda and the family Coral Crab. It is widely distributed in the Pacific and Indian Oceans, and lives among the branches of Acropora, a branching reef-building coral. The carapace is about 1.5 cm wide and has a slightly narrow rectangular shape at the back, with an extremely flattened shape. It is uniformly orange-red in color and has a porcelain-like luster. The calyx has four broad, wavy teeth, and there is a small spine in the center of the side edge of the carapace. The claws are large and different, but both have soft, fuzzy hairs on the outside of the palms. The walking legs are strong, with no claws at the tips of the phalanges. In addition to beautiful species such as the reddish-brown honeycomb-like T. reticulata and the red-spotted T. rufopunctata , which has many red circles, many closely related species are known, such as the black-brown T. digitalis . It is not thought that these crabs cause much harm to their host corals, but it is noteworthy that they only live among living coral trees.

[Masamichi Takeda]

Coral crab (ecology)
To protect themselves from predators, they make their home among the branches of Acropora coral reefs, which are highly safe. © Underwater Fort Enterprise, Isamu Soyama ">

Coral crab (ecology)

Reticulated coral crab (ecology)
Covered in a reddish-brown honeycomb-like mesh © Underwater Fort Enterprise, Isamu Soyama ">

Reticulated coral crab (ecology)

Giant red spotted coral crab (ecology)
There are many red dots © Underwater Fort Enterprise Isamu Soyama ">

Giant red spotted coral crab (ecology)

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

節足動物門甲殻綱十脚(じっきゃく)目サンゴガニ科に属するカニ。太平洋、インド洋に広く分布し、樹枝状の造礁サンゴであるミドリイシの枝の間にすむ。甲幅1.5センチメートルほどの後方がやや狭い四角形で、著しく扁平(へんぺい)。一様に橙赤(とうせき)色で、陶器のような光沢がある。額(がく)は幅広い波形の4歯で、甲の側縁中央部に小さな棘(とげ)が1本ある。はさみ脚(あし)は大きく、左右不同であるが、左右とも掌部(しょうぶ)外面にもやもやした軟らかい毛がある。歩脚はじょうぶで、指節の先端につめがない。赤褐色の蜂(はち)の巣状の網目で覆われるアミメサンゴガニT. reticulataや、赤い丸紋が多数あるオオアカホシサンゴガニT. rufopunctataなどの美しい種のほか、全体が黒褐色のクロサンゴガニT. digitalisなど多くの近縁種が知られている。これらのカニが宿主であるサンゴに多くの害を与えているとは考えられないが、生きているサンゴの樹間にしか生息しない点は注目に値する。

［武田正倫］

サンゴガニ（生態）
外敵から身を守るため、安全性の高いサンゴ礁のミドリイシの枝間をすみかにする©水中フォート・エンタープライズ　楚山いさむ">

サンゴガニ（生態）

アミメサンゴガニ（生態）

オオアカホシサンゴガニ（生態）

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

<<: The Memorial of the Three Kingdoms

>>: Struggle against the Sanko Rengo enterprise consolidation - Sanko Rengo enterprise consolidation anti-struggle