Category: Animals with Shells
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Janthina |
Small to medium-sized pelagic sea snails, commonly known as purple snails or violet shells. These snails live at sea-air interface. |
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Pteropods |
Small, swimming pelagic snails, commonly known as "sea butterflies." |
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Heteropods |
Molluscs with reduced shells, medial swimming fin, well developed eyes and a nearly transparent body; size to 300 mm. |