This is another beautiful nudibranch that I thought had completely eluded me.  But on closer inspection of a teensy teensy white bump on some algae, I discovered that I have indeed seen a juvenile of this species.  Terrible photo, but it’s here anyway.  If you look really closely you’ll see the “snowflakes” on its notum  — directly referencing its namesake: Poli’ahu, Mauna Kea’s  Goddess of Snow.  Thankfully, friends have seen this in its adult form, completely covered in a dusting of flakes.  Their individual was found in the same area (Ma’alaea Harbor) verifying its presence in the shallow, algae covered, exposed reefs available to snorkelers (and reef cleaners)  These can get to about 2 inches or 57 mm. The oversaturated juvenile documented here was no more than 10 mm (less than 1/2 inch).  Both individuals were found in less than 6 metres or 20ft of water.  For more information please see the  Sea Slugs of Hawaii.