How to Distinguish from Similar Species:
The sinuous line of contact between the terga and scuta distinguish this species from most other intertidal barnacles. Semibalanus balanoides
has a sinuous line of contact but also has no centripetal ridges at the interior base of the shell. Chthamalus dalli
has a straight, crosslike junction between the terga and scuta and the rostrum is overlapped by the rostrolaterals.