Need ID: which Bivalve? 4

[giovanni arusha]

Hi, can anybody ID this Bivalve?
<a href="http://www.badongo.com/pic/3168157" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/3168157">http://www.badongo.com/pic/3168157</a><!-- m --></a>
I got it in Zanzibar (Tanzania): it is about 1 cm in size.
Please need Latin and English names.
Many thanks in advance,
Giovanni

[paul monfils]

My first impulse was Pectinidae, and it might be. But after a little further consideration I suspect that this just might be a small juvenile Spondylus nicobaricus.