Chamaesipho columna (Spengler, 1790)
Phylum: Arthropoda
This is not a Mollusc. Other non-Molluscan Phyla (Echinodermata, Brachiopoda etc) have been included to help identify species that may be mistaken for Mollusca, but are not.
Classification:
Arthropoda (Phylum) > Crustacea (Subphylum) > Hexanauplia (Class) > Thecostraca (Subclass) > Sessilia (Order) >
Chthamalidae (Family) >
Chamaesipho (Genus) > columna (Species)
Distribution:
Intertidal on open coasts