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Tuskshells
 

The tusk shells or scaphopods are a class of marine mollusks which vary in size from minute to medium sized. The scientific name of this class is Scaphopoda, meaning "shovel-footed".

These molluscs live on soft substrates offshore (usually not intertidally). Because of this subtidal habitat and the small size of most species, many beachcombers are unfamiliar with them; their shells are usually not nearly as common or as easily visible in the beach drift as the shells of sea snails and clams.

Molecular data suggests that the scaphopods are a sister group to the cephalopods, although higher-level molluscan phylogeny remains somewhat unresolved.
The aragonitic shells of scaphopods are conical and curved in a planispiral way, and they are usually whitish in color. Because of these characters, the shell somewhat resembles a miniature elephant's tusk, hence the common name tusk shell. However, unlike an elephant's tusk, the shells of these molluscs are hollow and open at both ends; the opening at the larger end is the main or anterior aperture of the shell. The smaller opening is known as the apical aperture. Some tusk shells are minute, and most are 4 to 6 centimetres  long; however, a few species reach 15 centimetres  in length.

Tusk shells live in the bottom sediment where they feed.

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