Tusk Shell

Tusk shells, class Scaphopoda, are marine mollusks with a distinctive tapering, tube-like shell open at both ends, resembling a miniature elephant tusk, that they use to burrow tail-first into soft sea-floor sediment while leaving the narrow end projecting upward. They lack eyes and gills entirely, breathing through their mantle, and feed using thread-like tentacles called captacula that extend from the head to capture tiny food particles such as foraminifera from the surrounding sediment.