Difference in species of shells from shallow water and deep water also
depend on their food supply as well as their location.  I know of many
species that differ from shallow water to deep water.  But one that is
in shallow water in the Florida Keys is Cypraea cinera.  The ones that
live out on the reef in 3 to 20 feet are small and very dark, while the
ones that live under the bridges on the road to the Keys are often twice
as large and light colored. No deep water involved.

The deeper water Marginellas from South Africa have teeth on the inside
of the lip.  Also the cold water ones are different from the ones that
live in the warmer water on each side of the Cape.  I'm sure that Brian
or Bruno can really enlighten you on the variation.

A few species unfortunately have been designated new species just
because they are different because of their location and food supply.
This is just my opinion based on experence with dredged material from
the past years.  Which we can't hardly get anymore.  Those were the good
old days.

We have had some good Northwesters (wind) that have brought in a lot of
stuff.  There are thousands of Pen shells and purple sea whips etc. on
the beaches. I found an uncommon smooth channeled duck clam, Anatina
anatina (Spengler, 1802). still alive but one valve broken, too bad.

Bob

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