The barreleye fish, with its transparent head and extraordinary vision ... critical for survival in the pitch-black depths of the ocean where every light source and shadow matters. Bioluminescent ...

A humpback anglerfish (Melanocetus johnsonii)—a species known as a black seadevil—was spotted off the coast of Tenerife. This terrifying deep-sea fish is typically found at depths of 200 to ...