noun
helmet crab
A species of crab, Telmessus acutidens, known as the helmet crab. The name is usually written in katakana.
トゲクリガニは北海道の沿岸で見られる。
Helmet crabs can be found along the coast of Hokkaido.
The name トゲクリガニ literally means 'thorn chestnut crab', likely referring to its spiny carapace and resemblance to a chestnut. The exact derivation is uncertain.