gooseneck barnacle

noun2

1. •
   Any of the species Pollicipes pollicipes or P. polymerus, filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone, with a long and muscular stalk, which is edible and considered a delicacy in several Mediterranean countries.
2. •
   Any barnacle in the superseded order Pedunculata, now all or most of infraclass Thoracica, most of which are filter-feeders that attach to surfaces by a long stalk, though some are parasites.