I think everyone missed the most basic point. Cervus is only found in the United States, Mexico, Cuba, and Bermuda. The only Shells that they could be if they were found in Brazil Puerto Rico or the Bahamas would be zebra.
Scott 

Sent from my iPhone

> On Apr 24, 2020, at 6:42 PM, David Kirsh <[log in to unmask]> wrote:
> 
> Dear listers,
> 
> A longtime question for me: are there reliable distinguishing features between Macrocypraea cervus and zebra besides the dotted spots on the dorsum (and size)?
> 
> I’ve only managed to collect dead specimens with some weathering on their backs, possibly obscuring those dotted spots.
> 
> One is 59mm, probably zebra from Brazil.
> 
> Another is 91mm from Bahamas. A third is 93mm from Mona Island, Puerto Rico.
> 
> David Kirsh
> Durham, NC
> 
> 
> 
> Sent from my iPhone
> 
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