The female Lewis’ moonsnail (Euspira lewisii) egg collar is very distinctive in its appearance and is fairly substantial in thickness. The egg collar is made up of a combination of sand, mucus, and microscopic eggs.
This massive snail has a large round shell reaching 5.5 inches (14 cm) across! When the snail is fully extended it has a thick fleshy foot that wraps up onto its shell. This foot also serves as a plow to push through sand in the pursuit of clams and mussels. The Lewis’ moonsnail has a range from southern Alaska to northern Mexico.