|Also called: tooth shell any of various burrowing seashore molluscs of the genus Dentalium and related genera that have a long narrow tubular shell open at both ends: class Scaphopoda|
any of several marine mollusks of the class Scaphopoda. There are four genera of tusk shells (Dentalium is typical and most common) and more than 350 species. Most tusk shells live in fairly deep water, sometimes to depths of about 4,000 metres (13,000 feet); many deep-sea species are cosmopolitan in distribution
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