Ireland's wildlife logo.

Semibalanus

Acorn Barnacle (Semibalanus balanoides)

Barnacles are a common sight around Ireland’s rocky shores. These tiny animals form the familiar off-white patchwork that often covers large swathes of rock between the high and low water marks. Barnacles are crustaceans, relatives of crabs, shrimps and lobsters, although they were not firmly accepted as part of that….