This beautiful specimen of Goniobranchus sp. was photographed by Pirjo Pellet in Bima Bay, Sumbawa, Indonesia during a recent live-aboard trip on the Wunderpus.
It bears similarities with both Goniobranchus sp. 44 & sp. 45 in Gosliner, Valdes & Behrens, 2015 but there are differences. When compared to G. sp. 44 it lacks the light central & radiating lines but does feature the blue spots along the central line; however it has additional blue spots along the mantle margin and along the edge of the gill pocket. Furthermore the orange band on the rhinophores is located below the apex as per Goniobranchus sp. 45 with which it also shares the granular mantle texture similar to the host sponge. For the time-being I feel it is safest to simply call it Goniobranchus sp. until a full description of this species is published.
Pirjo uses a Nikon D 300 with a Nikon 60 mm, in a Sealux housing with Dual Inon Z-240 strobes. The settings for the shot here was ISO 250, f 20 at 1/160.
Pirjo Pellet along with her husband Francis (also an avid diver, photographer & videographer) live in Les Vans in the Rhone Valley, France. They have participated in many live-aboard dive trips as well as land-based holidays in the Indo-Pacific region. The Pellets are a pleasure to dive and travel with and, as you can see, their slug hunting and photography skills are superb. They probably don't need an introduction to readers of this site given their many contributions! A good many of their finds are in the 5 mm range, although this species was in the region of a massive 20 mm! Their results are outstanding - they cope beautifully with the focus and depth of field considerations which can drive the underwater photographer to exasperation. The Pellets, it goes without saying, excel in super macro photography of sea slugs!