Enw gwyddonol: Semibalanus balanoides
Barnacles are so common on our rocky shores that you've probably never really noticed them. They're the little grey bumps covering the rocks that hurt your feet when you're rockpooling. They're actually tiny little crustaceans and are related to crabs and lobsters!
YstadegauLength of shell: 2cm Average lifespan: up to 18 months