It lives in deep water near the US island of Guam in the western Pacific.
National Geographic Magazine says it's not seen very often and is a milky-yellow colour because it's so dark where it lives.
Professor Severus Snape is part of the name because he kept "one of the most important secrets in the story, just like the present new species which has eluded discovery until now, nearly 20 years after it was first collected".
Harry also refers to a famous biologist called Harry T Conley.
It's the latest creature to be given a name from fiction. Here are some of our favourites...
In December a group of scientists discovered the Eriovixia gryffindori.
It's named after the sorting hat from Harry Potter's fictional owner, Godric Gryffindor.
Then there's the Skywalker hoolock gibbon - and, yes, the scientists behind it are Star Wars fans.
The Chinese characters of its scientific name also mean "heaven's movement".
Skywalker's mate Chewbacca has had a hairy weevil named after him.
The Trigonopterus chewbacca is a flightless 3mm long beetle found off the coast of Papua New Guinea.
Three spiders have been named after Tobey Maguire and Andrew Garfield, in honour of their parts in the Spider-Man films.
There is the Filistata maguirei, the Maguimithrax and the Pritha garfieldi.
The Gabrius tolkieni, the Khamul tolkeini, the Leucothoe tolkieni, the Martesia tolkieni and the Shireplitis tolkieni are all named after author JRR Tolkien.
That's a beetle, wasp, crustacean, clam and another wasp.
We could write a whole separate page, or book, on species named after some of the characters.
Some of our favourites include Breviceps bagginsi, a frog named after Bilbo Baggins, the beetle Macrostyphlus gandalf and Gimlia, a wasp named after... you've guessed it... Gimli.
Gollum is probably the most popular though, including a fish called Galaxias gollumoides and a wasp called Smeagolia.