vermetidae?

[xavierb]

These are the beaches of Almeria Spain I have no more indications

[img width=343 height=480]http://www.badongo.com/t/800/12897220[/img]
[img width=341 height=480]http://www.badongo.com/t/800/12897223[/img]

[paul monfils]

These do appear to be Vermetidae, and there are certainly a few different species here.  There are at least 10 species of this family in the Mediterranean area, and they can be difficult to identify even when fresh, all the more difficult in worn beach specimens.  Also, there is very little good literature available on this family.