The dorsum surface is decorated with numerous brilliant orange-red bumps or pustules (hence the Latin name pustulata) surrounded by a dark ring.

These sea snails live in tropical to temperate waters at low tide to subtidal levels, and are usually found on coral reef or rocks.

They feed by night on stony corals (mainly Pocillopora species in the order Scleractinia), and rest during the day.

High predation by this corallivore gastropod was observed in July 2011 at a reef in the northern Gulf of California.

This sea snail is nocturnally active and hides during the day (Glynn, 1985), but during the immersions, individuals were always on the top of the coral colonies, moving and feeding at midday, as Paz-García and colleagues found.