Spiny Crab

Spiny Crab

Scientific name: Lithodes maia

Phylum: Arthropoda

Subphylum: Crustacea

Class: Malacostraca

Order: Decapoda

Description: The shell and legs of Atlantic king crab are heavily armed with sharp spines. Atlantic king crab has a pair of claws and three pairs of walking legs, and the 4th pair of hind legs hidden beneath abdomen. The size of Atlantic crab can reach 100mm.

Distribution: Spiny crabs are boreal deepwater crabs, normally at depths more than 200ft.

Locomotion: Spiny crabs primarily move forward by flexion and extension of limbs.

Food gathering: Spiny crabs are predators. They grasp prey with enlarged front claws followed by tearing, grinding or shearing with various mouth parts. They eat live prey but also scavenge on dead animals.

Gas exchange: Atlantic crabs have gills in branchial chambers for gas exchange. They use gill bailers (elongate exopods) that vibrate to create ventilating currents.

Reproduction: Scattered individuals find one another during mating season using environmental cues. Sperm are deposited directly into oviduct and females brood eggs until hatching occurs. The swimming larval stages are known as zoea.

Interesting facts: Spiny crabs are related to hermit crabs and their zoea larvae resemble those of hermit crabs.