Common throughout the Solitary Islands Marine Park. Widespread distribution through the Indian Ocean from South Africa to Australia, western Pacific region to Hawaiian Islands. In Australia recorded from Perth in Western Australia north to the Timor Sea, the Coral Sea and Great Barrier Reef in Queensland, south to eastern Victoria and including Lord Howe and Norfolk Islands.
Frequents shallow reefs and lagoons where it feeds on algae and sea grasses. Often found with algae or shell fragments adhering to dorsal surface, possibly as camouflage. Depth to 75 m.
Recent studies on the east coast of Australia reveal that Tripneustes kermadecensis and Tripneustes gratilla exist sympatrically. The "Lamington" urchin, at the top and fourth photo is T. kermadecensis, the second photograph shows T. gratilla, while the third photograph shows a possible hybrid between the two. These species are the subject of commercial research, where they are grown for human consumption or to reseed areas that have been depleted. Grows to a test diameter of 150 mm with a spine length of around 15 mm.
Identification of photographs thanks to Dr Maria Byrne, Professor Marine and Developmental Biology, University of Sydney, NSW, 2006, Australia.
Graham J. Edgar. Australian Marine Life, 2nd Edition, 2008. Reed New Holland Publishers. pp.418-9.
Davie, Peter. Wild Guide to Moreton Bay and Adjacent Coasts. Second Edition. Published by Queensland Museum. Vol 2, p.275.
Atlas of Living Australia website at https://bie.ala.org.au/search?q=tripneustes+gratilla. Accessed 14/10/2018.