This creature is called both a Red Batfish or Starry Handfish (Halieutaea stellata). Here it’s eating bait at Enoshima Aquarium in Fujisawa, Japan, but they are normally found “on the continental shelves of the Indo-Pacific oceans at depths of between 50 and 400 m. They are up to 30 cm long.”
This is what it looks like when it swims:
More from Enoshima Aquarium: transparent leptocephalus and time lapse of a molting Japanese Spider Crab.
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