Small black, tall spired shell with axial ribbing. It has a circular, horny, mud brown operculum. Smaller and darker than Z. lutulentus.

Mudflats, muddy rocks and tide pools in the mid -intertidal.

Passes mud through the gut to extract nutrients.

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Guide to Common Intertidal Species of the South Island; Scheil NZ Coastal Marine Invertebrates; Vol 1