Dear Jorge,
 
You are a bit confused.  Marginella hematita, is actually Eratoidea
hematita (Kiener, 1834). It is a Caribbean Marginella.  Mine were
dredged in the Gulf of Mexico.  They are red to reddish brown.  Size is
9-12 mm.  I think the shell you are thinking about is from West Africa.
It is Marginella helmatina Rang, 1832.  19-25 mm.  The shell that was
mistakenly called helmatina has been named Mar. senegalensis Clover,
1990.  Write to me personally is you want more information.
 
Dear James,
 
A far as apicinum goes.  I'm quite amazed that you have not found Prunum
apicinum.  They are in tampa Bay by the thousands.  Go at low tide
Winter or Summer, and just keep walking.  Sooner or later you will find
a dead crab or half eaten clam or a dead fish and the apicinum will be
everywhere.  It's the other Marginella that are not as easy to find.  We
have 7 species that are found in Tampa Bay.
 
Bob Lipe
 
 
www.theshellstore.com
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