Grapsid

Grapsid is a common colloquial term referring to crabs belonging to the family Grapsidae. These crabs are a diverse group, typically found in marine and brackish water environments worldwide. They are characterized by their square-shaped carapace, which is often wider than it is long, and their relatively short legs.

Grapsid crabs are known for their strong claws and their ability to move sideways with great agility. Many species are intertidal, meaning they inhabit the area between high and low tide marks. They can be found on rocky shores, in mangrove forests, on coral reefs, and even in association with human structures like piers and seawalls. Their diet is varied and can include algae, detritus, small invertebrates, and sometimes carrion, making them important scavengers in their ecosystems.

Reproduction in Grapsid crabs typically involves external fertilization, with females carrying their eggs attached to their pleopods. The larval stages are planktonic, drifting in the water column before settling and metamorphosing into juvenile crabs. Some species exhibit distinct behaviors, such as territoriality or specific foraging strategies, which contribute to their ecological roles. Due to their widespread distribution and adaptability, grapsid crabs are a significant component of coastal and marine food webs.