This is a beautiful dendronotus that is rarely rarely seen — so rare that inaturalist.org has only one other observation, documented in 1986 in Oregon. At first glance it appears to be a Bushy Back Nudibranch, but if one looks closely it has a white margin on its large foot, is generally larger (up to 60 mm — 2.5 inches ) and has very marked white spots that extend to its rhinophores, oral tentacles and branches.