Trivirostra oryza (Lamarck, 1810)

Distribution: 

Uncommon in the Solitary Islands Marine Park. Distributed throughout the tropical Indo-West Pacific region. In Australia, reported from Shark Bay in Western Australia, across the tropical north, the Coral Sea and Great Barrier Reef in Queensland south to southern New South Wales.

Ecological Notes: 

Found on the under surfaces of rocks and coral rubble. Associated with soft brown encrusting ascidians upon which it feeds. Specimen pictured, bottom photograph, discovered in intertidal rock pool.

Additional Notes: 

The shell is pure white, the mantle is predominately black or brown and blends well with its food source. The foot has opaque white lines. Rarely found alive possibly due to its small size and cryptic nature. Grows to 11 mm, specimen in lower picture approximately 8 mm long.

References: 

Coral Reef Animals of the Indo-Pacific, Terrence M. Gosliner, David W. Behrens and Gary C. Williams, Sea Challengers Publication, Monterey, California. 1996. p.140.

Atlas of Living Australia website at https://bie.ala.org.au/search?q=trivirostra+oryza. Accessed 12/11/2018.

The Seashells of New South Wales, Des Beechey, Senior Fellow, Australian Museum, Release 25. Website at https://seashellsofnsw.org.au/Triviidae/Pages/trivia_oryza.htm. Accessed 12/11/2018.