Japanese spider crab

Macrocheira kaempferi

The Japanese spider crab has extremely long legs and a small, rough body. It lives on rocky seafloors around Japan and can become the largest arthropod by leg span.

Not a fish · an aquatic neighbor

Water

Saltwater

Rocky and sandy seafloor, caves, and submarine slopes.

Temperature

Range not established

A dependable species-specific wild temperature range was not established from the reviewed sources, so both values are null.

Size

Leg span up to about 3.7 m (12 ft)

Wider than a tall refrigerator

Lifespan

Best-supported wild lifespan is not established.

Life expectancy varies with place, conditions, and what scientists have been able to observe.

01 · Signature adaptation

What does it do?

It walks slowly across the bottom and may gather seasonally for breeding. Young crabs molt repeatedly while their long legs develop.

Its superpowerIts long jointed legs let it walk across rugged deep-water terrain.

02 · Home coordinates

Where does it live?

Pacific waters around Japan, especially Honshu and nearby islands.

Regions: Northwest Pacific · Coastal Japan

03 · The menu

What does it eat?

It uses its claws to collect both plant material and animals from the seafloor.

Omnivore and scavenger: mollusks, algae, fish, detritus, carrion.

04 · Remember this

Two wow facts

Arthropod record-holder

Its leg span can exceed that of any other known arthropod.

Sources [1]

Camouflage collector

Young spider crabs may attach organisms to their rough shells, helping them blend with the seafloor.

Sources [2]