Sally Lightfoot Crab

Description:

G. grapsus is a typically shaped crab, with five pairs of legs, the front two bearing small, blocky, symmetrical chelae. The other legs are broad and flat, with only the tips touching the substrate. The crab's round, flat carapace is just over 8 cm (3.1 in) in length. Young G. grapsus are black or dark brown in color while adults are brightly colored. Some are muted brownish-red, some mottled or spotted brown, pink, or yellow. The ones seen on photographs of tropical island fauna are often bright orange or red with stripes or spots dorsally, blue and green ventrally, and sporting red claws and pink or blue eyes.

Habitat:

It is found along the Pacific coast of Mexico, Central America, South America (as far south as northern Peru), and nearby islands including the Galapagos Islands. This crab lives amongst the rocks at the often turbulent, windy shore, just above the limit of the sea spray. It feeds on algae primarily, sometimes sampling plant matter and dead animals.