Japanese spider crab

Macrocheira kaempferi · The Japanese spider crab is a giant marine crab found in the waters off southern Honshū, Japan, and it has the largest leg-span of any arthropod.

Japanese spider crab
Photo: Tsarli at English Wikipedia, CC BY-SA 3.0
Japanese spider crab
Photo: Joseolgon, CC BY-SA 4.0
Japanese spider crab
Photo: Lycaon (Hans Hillewaert), CC BY 2.5

Taxonomy

KingdomAnimalia
PhylumArthropoda
ClassMalacostraca
OrderDecapoda
FamilyMacrocheiridae
GenusMacrocheira
SpeciesMacrocheira kaempferi

Where it lives

Deep waters off Honshu, from Tokyo Bay to Kagoshima, and near Taiwan.

Fun facts

  • From claw to claw, a Japanese spider crab can stretch up to 3.7 metres, the greatest leg span of any known arthropod.
  • Despite its fierce look, this giant crab is reported to be gentle.
  • To hide from predators, the crab decorates its shell with sponges and other animals, so its bumpy shell blends into the rocky sea floor.
  • A female can lay up to 1.5 million eggs in one season, and the eggs hatch in about 10 days on average.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).