Beachcombers Field Guide - Department Of Fisheries Western ...

Acorn barnacle
Arthropoda – Cirripedia
Acorn barnacles have
free-swimming larvae that attach
themselves head-down onto hard
surfaces, including rocks, jetties, boat
hulls and even other marine animals and
plants. As they grow, their external shell
becomes a series of plates, and jointed
legs develop into feathery appendages
that trap plankton for food.
Did you know?
Barnacles are hermaphrodites
– they have both male and
female sexual organs. Barnacles
can fertilise one another by using
an extremely long penis or, if
separated by long distances, they
can fertilise themselves!