Oxygyrus Keraudrenii is a species of Sea Snail, a holoplanktonic marine gastropod mollusk in the family Atlantidae. 

This is a large, dextrally shelled, pelagic snail, 1cm in diameter with large eyes and a single swimming fin. The keel and teleoconch are not calcareous but formed of cartilage-like substance. There is only onewhorls visible, the others are visible in the umbilicus. The brows shell is strongly flattened and keeled. The spire of the operculum is strongly excentrical. It is a carnivorous species predating on relatively largezooplankton. This species occurs in the warm waters of all oceans.

Sources :

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