Is it possible to have a virtually white Mca. nigritus?  Cuz I have a shell here that I found in a bix of odds and ends my dad had from his childhood, and it matches the form of M. nigritus, as far as the placements of major spines, spire and aperture shape, varices, etc.  The only problem is it is completely off-white except for a few dark patches on the first couple of body whorl shoulder spines.  It is also kind of small for what I've seen avg sp sizes listed, 40 mm (cf ~75-150 mm), although it could always be a juvie I spose.  I saw on a website (Shells of CA and Baja Mex) a picture of a white M. nigritus so it gives me an idea that I may not be totally wrong with my guess.  If there are white forms, is it a common thing?

 

~Stephen~