It grows to about one foot in length though 15 inches has been recorded. After the shell reaches eight to nine inches, the colors fade to an overall grayish white. Females are generally larger than males, so the record setters are probably of the former gender. They are fairly common, except for right-handed specimens. Illustration by Walter W. Hunt 1999.
Lightning Whelks live in sandy shallows from below the tide mark to deeper waters.
These predatory carnivores bury themselves just under the surface of the sand where tender mollusks they like to eat are easy to find. Clams, scallops and oysters are favorites. The whelk attacks its prey in two ways. Either it grabs the bivalve with its big foot and pounds it apart on its own strong shell, or it inserts the outer lip of its own shell between the valves to force them apart. Beginning in spring, strands of whelk egg capsules wash ashore.