Acorn barnacle
- kingdom: Animalia
- phylum: Arthropoda
- class: Maxillopoda
- order: Sessilia
- family: Chthamalidae
- genus: Chthamalus
- species: Chthamalus fissus
Dana Point- Isla Vista
- Malibu
- San Diego
California
United States
Acorn barnacle Dana Point Isla Vista Malibu San Diego