Invertebrates
Moon Snail
Neverita · also called moon snails
A moon snail wraps its oversized foot around a clam, pins it in place, and begins the slow work of drilling a neat, round hole straight through the shell using an acid-coated tongue. Hours later, the clam is gone, and the telltale hole left behind is often the only evidence anyone finds of what happened.
Overview
The moon snail, genus Neverita, is a large, sand-burrowing predatory sea snail found on sandy seafloor habitat in oceans worldwide. It drills through bivalve shells using acid and a rasping radula, a slow but reliably effective hunting method.
A calling card left on every beach
The distinctive round drill-holes moon snails leave behind in empty clam shells are among the most recognisable predator signatures beachcombers encounter, quiet evidence of a hunting method that leaves nothing to chance once it begins.
Status
Least Concern — common and widespread across suitable sandy seafloor habitat in oceans worldwide.
Moon Snail: common questions
How does a moon snail actually kill its prey?
A moon snail envelops a clam or other bivalve in its large, fleshy foot and then uses a specialised acid-secreting organ combined with its rasping radula to slowly drill a neat, nearly perfectly round hole through the prey's shell, a process that can take many hours before the snail can finally reach and consume the soft tissue inside.
What is a sand collar and why do moon snails make them?
A sand collar is a distinctive circular structure made of sand held together by mucus, produced by a female moon snail specifically to house and protect her eggs during development, and these collars are a recognisable and frequently encountered sight washed up or embedded on sandy beaches during the species' breeding season.
How can you tell if a shell was a moon snail's meal?
A shell drilled through by a moon snail typically shows a small, neat, nearly perfectly round hole, a distinctive and recognisable sign of moon snail predation that beachcombers frequently find on the empty shells of clams and other bivalves washed up along sandy shorelines.
Why does a moon snail have such an oversized foot?
A moon snail's unusually large, fleshy foot can expand to nearly engulf its own rounded shell, serving a dual purpose of smothering and immobilising prey during an attack while also allowing the snail to burrow efficiently through loose sandy sediment as it searches for buried clams.