New Zealand pea crab

New Zealand pea crab
Stage V adult female
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Brachyura
Family: Pinnotheridae
Genus: Nepinnotheres
Species:
N. novaezelandiae
Binomial name
Nepinnotheres novaezelandiae
(Filhol, 1885)

The New Zealand pea crab (Nepinnotheres novaezelandiae), is a species of small, parasitic crab that lives most commonly inside New Zealand green-lipped mussels. Adult females are about the size and shape of a pea, while adult males are smaller and flatter. Adult New Zealand pea crabs are completely reliant on their host mussel for shelter and food, which it steals from the mussel's gills. The New Zealand pea crab is found throughout New Zealand and can infect up to 70% of natural populations. These crabs are of concern to green-lipped mussel aquaculture because they reduce the size and growth of mussels, although infected mussels can be harvested and consumed.