Help ID small pink shell w black and white spiral?

[paul monfils]

This shell is a member of a very large family of marine shells called "Trochidae", commonly known as "top shells".  This particular genus of top shells is called "Umbonium", and are commonly known as "button top shells".  The one you have is the commonest species of button top, scientific name "Umbonium vestiarium", common name "common button top".  It is very common throughout the tropical Indo-Pacific region. This species occurs in a great variety of colors and patterns, some of which you can see here:

http://www.conchology.be/?t=66&family=&k...on_species=

http://www.gastropods.com/8/Shell_258.shtml

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