>According to the Kaicher card set on Neritidae, it is both.  Smaragdia
>viridis (Linnaeus, 1758) is from the Mediterranean and has scattered white
>blotches on green, an incurved, dentate columellar lip, and grows to about
>8mm.  Smaragdia viridimaris (Maury, 1917) is from S.E. Florida and the
>Caribbean, has white blotches but also a white band bordering the columellar
>shield, a whitish operc, and grows to 6mm.

I have a few (traded) specimens from the Mediterranean that show also the
white band bordering the columellar shield. The Caribbean ones have a very
green operculum. Both the Mediterranean and Caribbean groups sometimes have
black markings as well and I've seen a few Caribbean ones with red streaks.
All this serves to camouflage them well on their green algae stalks and
it's quite a challenge to spot the shells in situ (you have to snorkel and
focus carefully). The animal is also green.

One lot of Mediterranean shells came with the name Smaragdia viridis
producta (no author). They're larger than the other lot. Both are beach
collected.

I'm sending Tom some shells from Andros, Bahamas, some with opercs.

Peggy

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