Goniobranchus geometricus (Risbec, 1928)


Uncommon in the Solitary Islands Marine Park. Found in tropical Indo-West Pacific, including Sth Africa, the Maldives, Japan, Okinawa. In Australia known from Western Australia, Queensland, northern New South Wales and Lord Howe Island.

Ecological Notes: 

Found on rocky reef, feeds on sponges including Chelonaplysilla violacea.

Additional Notes: 

Best recognised by the violet/black lines on the mantle and the yellowish/green gills and rhinophores. Grows to around 30 mm.


Gary Cobb, David Mullins, Nudibranchs Encyclopedia, 2nd Edition, 2015. Publishers Thomas Slone, Masalai Press and Tim Hochgrebe, Underwater Australasia. p.136.

Australian Museum, Sea Slug Forum. http://www.seaslugforum.net/showall/chrogeom. Accessed 07/08/18.