This snail can be found in large numbers in the tidal zone, on or underneath
stones. It has a strong shell, with several whorls. The shell can be closed with
an operculum. The shell is typically grooved, which can be less obvious with
older specimens because of wear. They feed on algae that they graze of rocks and
stones. After fertilization the eggs with a diameter of 1 mm are released into
the water. After 1 week the eggs will hatch. The larvae are planktonic the first
few weeks. After they reached the seafloor, the journey to the shore starts.
About 35 mm tall.
Dark green to greyish brown, can be bleached by the sun.
In the tidal zone.
North Atlantic, in Europe from the White sea till north Spain.