Salmacis sphaeroides (Linnaeus, 1758)
Uncommon in the Solitary Islands Marine Park. Distributed throughout the tropical Indo-Pacific region. In Australia recorded from Albany in Western Australia, across the tropical north, throughout Queensland and south to around Sydney in New South Wales.
Frequents subtidal areas of algal growth and detritus, to a maximum depth of 90m.
Distinguished by the brown/green test with banded spines. May collect detritus from the substrate which is used for camouflage or shade. Grows to around 8cm.