Details
Macrocheira kaempferi
The Japanese spider crab is one of the world's largest crabs, living in Pacific and Palearctic waters. It is a solitary omnivore that walks on long legs across the seafloor.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
It uses deeper seafloors of the northwest Pacific, including waters around Japan. Sandy-muddy bottoms and nearby rocky cover are typical.
Leg span is about 150-380 cm, with weight about 10-19 kg. A relatively small body carries extremely long legs, often orange with pale markings.
It is solitary and treated here as diurnal. It moves slowly along the bottom, and is especially vulnerable after molting until the shell hardens.
It is omnivorous, taking animal matter, shellfish, and carrion from the seafloor. Its long legs help it search over a broad area.
Females carry fertilized eggs under the abdomen. Larvae hatch into the water column, then develop through molts before settling to bottom life.
Its conservation status is LC. Despite its spectacular size, it is a quiet inhabitant of deeper coastal seafloors.
