I've looked throught the specimens of Neverita duplicata here and can
contribute some observations. I find specimens that match Phil's Neverita
sp., all from the US Gulf Coast, except for one lot from Lake Worth,
collected by Tom McGinty. The channeled umbilicus seems distinctive.
Specimens of Neverita duplicata from New Jersey have golden brown
periostracum in the umbilicus, although not as brightly colored as in the
Florida specimens (and the specimens from NJ were collected 30 years later).
 
If this form proves to be a different species, then it is Neverita fossata
Gould, 1847 (type locality Florida). Gould stated "This would not at first
sight, be distinguished from _N. duplicata_ Say, which it greatly resembles
in form and coloring, but the umbilical region is entirely different; and
the deep wide channel leading to the umbilicus bordered by an acute ridge,
and covered by a spirally striated epidermis is in striking contrast with
the pale polished region adjacent."
 
Gary
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Gary Rosenberg, Ph.D.                     [log in to unmask]
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