Johan,
 
Engina corinnae was named from specimens collected off Spondylus americanus
collected by divers at 100' depth off Palm Beach in Florida. I have never
seen any from shallow water, especially snorkel depth, except a few beach
specimens from the Yucatan peninsula in the Tulane collection. The only
engina I have ever found (in nearly 30 years of collecting at least once a
year in the Florida Keys) in the Keys is Engina turbinella. The suggestion
of juvenile Cantharus is quite possible, unless your shells have a
thickened lip with teeth as most Enginas do.
Farther south in the Caribbean there is Engina karinae (Usticke), which is
basically white with gold colored bands and some dark markings. It's a very
delicate shell and was named as a bailya.
There is also an unnamed Engina in the Gulf of Mexico but I haven't seen it
from the Keys either.
 
Peggy Williams
 
                  Shell Collecting Trips Around the World
Visit my website at http://www.mindspring.com/~shellelegant
                                  Peggy Williams
                                   Shell Elegant
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