Sea Elephant, Heteropod, Carinariidae, Cardiapoda placenta, Pterotracheoidea, Black Water diving over Gulfstream Current; Florida Atlantic Diving; Plankton; SE Florida Atlantic Ocean off West Palm Beach; larval fish; marine life; pelagic creatures; pelagic larval marine life; vertical migration marine creatures, The Pterotracheoidea is, according to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), a taxonomic superfamily of sea snails or sea slugs, marine gastropod molluscs in the clade Littorinimorpha. They are commonly called heteropods or sea elephants.