Fantasy Creature Design of an Underwater Photosynthetic Whale

Imagined non-existing prehistoric survivor blending amphibian and cetacean traits, small dog-sized, depicted in natural history illustration style in a floating sky islands habitat. Anatomically believable design — coat, scales or skin texture coherent, eyes and limbs in plausible proportions. Single creature, calm posture, environment provides natural lighting and scale reference. No humans. No animal cruelty, injury, blood or gore. No monster-of-the-week horror — this is a wildlife-style render of a believable invented species. Specifically: underwater photosynthetic whale. Target search intent (rendered visually, no on-image text): "fantasy creature design" (en).