A heavily encrusted individual. The anterior slit is still visible.
This keyhole limpet is white in colour, with a sculpture of axial ribs transected by concentric ribs, which form a lattice pattern with deep pits. Its apex curves backwards to a sharp point and does not have an aperture. Instead there is a slit from the front edge of the shell inwards a short way. This species is similar to several limpets and false limpets, but its distnctive sculpture and anterior slit distinguish it. Very similar in apperance, and also a fissurellid, Montfortula rugosa does not have the concentric ridges, and although it has an anterior slit, it is very short and only noticeable from the underside of the shell.