What is "spider crab"

Macropod \Mac"ro*pod\, n. [Macro- + -pod.] (Zo["o]l.) Any one of a group of maioid crabs remarkable for the length of their legs; -- called also spider crab.

n. Any of various species of crab of the family ''(taxlink Majidae family noshow=1)'' with long leg.

n. any of numerous crabs with very long legs and small triangular bodies