Japanese Spider Crab (Macrocheira kaempferi)

The size of the Japanese spider crab makes it a weird animal. It is the largest living crab in the world. The carapace of the Japanese spider crab is 12 inches wide, but its legs can grow up to 13 feet long. It has an average weight of 20 kg and can live up to 100 years old.

The legs keep growing even when the crab reaches adulthood. They have ten long legs, eight walking legs, and two chelipids. Chelipeds are crab legs with claws. In the male crab, chelipeds are longer than its walking legs, while the female crab’s are shorter than its walking legs. 

You can find these crabs on Japan’s Pacific Coast. They prefer sandy and rocky continental slopes. Japanese spider crabs are scavengers of the ocean. They spend most of their time scavenging for decaying fish, invertebrates, and algae on the ocean floor. Also, they are not swimmers. They walk on the ocean floor slowly.