New piranha-like fish with 'human teeth' and Eye of Sauron marking found deep within the Amazon

A new species of piranha-like fish has been discovered in the Amazon River after secretly masquerading as another, nearly identical species for almost 200 years. Scientists have named the newfound fish after the dark lord Sauron from J.R.R. Tolkien's fantasy epic "The Lord of the Rings." 

However, the fish is nowhere near as scary as its sinister moniker implies.

The newly identified species, Myloplus sauron, is a pacu — a close relative of piranhas that are often confused for the iconic freshwater fish. Researchers discovered M. sauron while studying the nearly identical species M. schomburgkii, which was first discovered in the Amazon in 1841 but has largely been ignored by scientists since then. 

In a new study, published June 10 in the journal Neotropical Ichthyology, scientists performed a genetic analysis of the M. schomburgkii population, which revealed that it was actually made up of three distinct species: M. schomburgkii, M. sauron and M. aylans. After closely examining the fish, the researchers also noticed nearly imperceptible physiological differences between the three species, including the number of vertebrae and dorsal fin rays, and the shape of the anal fins in females.

M. sauron, which was described alongside M.aylans in the new study, is named for a black band on its side. This stripe, which is also present on M. schomburgkii and M. aylans, bears a striking resemblance to the "Eye of Sauron" — a gigantic fiery eye controlled by the titular villain.   

"Its pattern looks a lot like the Eye of Sauron, especially with the orange patches on its body," study co-author Rupert Collins, the senior curator of fishes at the Natural History Museum in London, said in a statement. "As soon as one of my colleagues came up with the name for this fish, we knew it was perfect for it."

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