Updated: Aug 5, 2021
The Faceless cusk eel or Typhlonus nasus is a blind fish (not a real eel) with tiny eyes on the underside of its head and buried under its skin. It was first seen in the late 1800s in Australia on August 25th, 1874 and found again more than a century later on May 15, 2017. So much time had passed that when it was found again some scientists thought it was a new species.
It is widely distributed from the Arabian Sea to Hawaii, although it is very rarely seen. It lives in a depth of 3935 - 5100 m (12,910 to 16,732 ft), in enormous pressures and freezing temperatures.
As mentioned, its eyes are located underside the head and under its skin. Its mouth is underneath its body. These combined characters make it seem like it has no face. It can grow to 28.5 cm (11.2 in), almost the size of a ruler. Even though it seems very slime-looking fish, it is a vertebrate.
Its mouth is relatively small and filled with close-set teeth. According to researches, scientists believe they eat a variety of crustaceans. Below are some pictures of its mouth and teeth:
Like other deep-living creatures that are rarely found, there isn’t so much research on the Typhlonus nasus. In my opinion, its popular name should be hidden face instead of faceless, because it does have eyes, a mouth, and a snout, they are just hidden.
https://fishesofaustralia.net.au/home/species/5354 https://www.livescience.com/59484-faceless-fish-rediscovered-photos.html https://www.mindat.org/taxon-2345928.html https://www.scienceandthesea.org/articles/201801/faceless-fish-deep-deep-sea