Does anyone know what this is?

[Grahambo]

I found this in Costa Rica and do not know what it is.  I attached a couple pictures.  It is a small V shaped shell like piece.  I looks like it fits together with other similar type pieces but looks like it has detached.  It does not appear to be broken.  A Tico in Costa Rica told me it was part of a conch shell but I can't find anything that would suggest this is true.

Any help would be greatly appreciated.