Possibly one of the most interesting, well known and intimidating of pioneering naturalist William Beebe’s mystery fish is the Bathysphaera intacta.
On November 22nd, 1932, Beebe was eight kilometres off Nonsuch Island in Bermuda, 2100 feet below the surface. While peeping through the windows, he saw two bizarre fish illuminated by the bathysphere’s lights about eight feet away. They were about six feet long, with slender barracuda-like bodies and large overbites, featuring dozens of disproportionately large teeth. On the side of the fish were horizontal rows of 20 glowing photophores. Hanging beneath both fish were two long “anglers”, one below the jaw and the other below the anus.
Beebe speculated that the B. intacta were an unknown species related to black dragonfish, which were very similar, albeit about seven times smaller. No other sightings of B. intacta have been recorded, though this is unsurprising given their inaccessible habitat.