Hyperstrophic Turbo smaragdus Gmelin, 1791

    Note the clockwise growth of the operculum (viewed from its attached surface). This is the topology of a dextral animal; The spiral operculum of a truly sinistral animal would exhibit counter-clockwise growth.

    Images by Andrew Grebneff (Dunedin, New Zealand) | Specimen from The Museum of New Zealand (NMNZ) (about 50 mm.)