Identification

[paul monfils]

This looks like a Coralliophila, but I can't name the species with certainty.  It could be a large, slightly worn specimen of C. costularis.  I have seen some that looked similar to this.

http://www.conchology.be/?t=68&u=354787&...c503a5268f

Another possibility is Coralliophila turrita, an uncommon species with little data available.  Your shell looks like this one:

http://vwargnier.free.fr/Pages2/512.htm

but not like this one, which is supposedly the same species:

http://www.conchology.be/?t=68&u=494383&...80889464e6

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