Sand Crab Sacculina

Sacculina granifera


Sand Crab Sacculina, Sacculina granifera, protruding from underside of crab

Large, leathery, twin lobed sac protruding from underneath crab's abdominal flap. To 70 mm across sac.


Significant parasite of commercial Sand Crab. The 'sac' is the egg-producing body of the parasitic barnacle that lives inside crab. Hormones secreted by barnacle lead to castration and feminisation of host crab (changing males into females). This causes the crab to nurture the barnacle egg mass as its own.

Indigenous to subtropical eastern Australia.

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Of Interest