Photographer: Paul Osmond
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One of several similar looking nudibranchs, this is considered the proper color form of the chromodorididae nudibranch Mexichromis multituberculata. This individual was seen moving across the rich, black soil on the ocean floor on the Tulamben Slopes dive site in Tulamben Bay in Bali, Indonesia.
Tulamben Slopes is one of the premier muck diving sites in the world, featuring black sand slopes that are some of the richest in the world.