They don't look like a crab but actually look like a giant tortoise with a jewel-encrusted shell. When they are threatened, they will expel a stream of flame from its rear end. Strictly protected by magical law, they live on certain beaches in Fiji, which are shielded with various forms of repelling charms.

The shell is also prized by wizards for magical cauldrons. Crossbreeding a Fire Crab with a Manticore is rumoured to create an ugly, vicious beast called a Blast-Ended Skrewt. These creatures can be domesticated but require a specific license.