Nerita plicata (Linnaeus, 1758)

Distribution: 

Uncommon in the Solitary Islands Marine Park. Abundant in tropical Indo-West Pacific, declining in abundance at edges of range. On the east coast of Australia south at least to Woolgoolga in New South Wales.

Ecological Notes: 

Found on intertidal rocky shores.

Additional Notes: 

Shell with low spire, width equal to or less than height. Sculptured with about 16 strong spiral ribs. Columellar deck lirate, columella convex, with three strong denticles centrally. Outer lip with large denticle at top, another at bottom, with 3-4 elongate denticles between. Exterior dull  white, fawn or pink, ribs sometimes spotted with black. Operculum calcareous, brown, columellar deck white, aperture white. Members of this family frequently found in crevices or amongst weed on rocky shores where it feeds on a thin layer of algae on rock surfaces. The ridges on the shell help to radiate heat from the sun. Grows to 30 mm in height.

References: 

The Seashells of New South Wales, Des Beechey, Senior Fellow, Australian Museum, Release 25. Website at https://seashellsofnsw.org.au/Neritidae/Pages/nerita_plicata.htm. Accessed 09/11/2018.