Halloween crab

Gecarcinus quadratus · Gecarcinus quadratus (the Halloween crab) is found in various locations across the Pacific and Atlantic coasts of the Americas.

Also called Halloween moon crab, Harlequin land crab.

Halloween crab
Photo: Charles J. Sharp, CC BY-SA 4.0
Halloween crab
Photo: Thomas Splettstoesser, CC BY-SA 3.0
Halloween crab
Photo: Dexxfire, CC BY 3.0

Taxonomy

KingdomAnimalia
PhylumArthropoda
ClassMalacostraca
OrderDecapoda
FamilyGecarcinidae
GenusGecarcinus
SpeciesGecarcinus quadratus

Where it lives

Coastal forests and mangroves on the Pacific coast from Mexico to Peru.

Fun facts

  • This nocturnal crab digs its own burrows that can stretch as long as 1.5 m (4.9 ft).
  • Even though it always stays near water, this crab can't actually swim.
  • It's largely vegetarian, munching on fallen leaf litter and tender seedlings.
  • Male Halloween crabs have noticeably larger carapaces than females, up to 6 mm (0.24 in) wider.

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