Click the thumbnail photos to enhance!
I label it Pseudocerotidae sp. 15, because my best guess is that it should be placed in the family Pseudocerotidae Lang, 1884.
It is characterized by a whitish background colour with numerous irregular dark brown patches along the median line, by a broad diffuse translucent orange mantle margin, by orange pseudotentacles, and by an orange spot at the posterior end.
I am not sure whether these two specimens of of the same species, their general appearance is pretty similar.
Maybe this is a very strange variant of Pseudoceros scriptus.