Echinometra mathaei (Blainville, 1825)
Common in the Solitary Islands Marine Park. Distributed throughout tropical Indo-West Pacific region. In Australia recorded from the south west coast of Western Australia, around the tropical north to southern New South Wales on the east coast, and including Lord Howe and Norfolk Islands.
Prefers shallow habitats where it bores into the rock or reef substrate where it often forms large aggregations in zone of greatest wave action, just below the low water mark. Herbivorous, feeding on algae. Depth from 0 to 34 m.
Often grey or brown with short, stout spines, usually with a white circle around the base and often with a white tip. Test diameter to 85 mm, spines to around 30 mm.
Graham J. Edgar. Australian Marine Life, 2nd Edition, 2008. Reed New Holland Publishers. pp.420-1.
Atlas of Living Australia website at https://bie.ala.org.au/search?q=Echinometra+mathei. Accessed 10/10/2018.