(CN) – For more than 250 years, scientists have known about the electric eel. But in a study released Tuesday, researchers revealed the discovery of two new species that could change our understanding of the unique creatures.
The study, published in the journal Nature Communications, reveals new information about electric eels that scientists say “opens up new avenues of research into the origin and production of strong electric discharges in other fish species.”
Electric eels, also known as naked-back knifefishes belonging to the gymnotidae family, are unique in that they are related more closely to carp and catfish than other families of eels.
Native to the fresh waters of South America and Mexico, the gymnotiformes are mostly nocturnal and use weak electric fields for navigation and communication as most have small eyes that are not well suited for sight.
“The electric eel, which can reach 2.5 meters in length, is the only fish that produces such a strong discharge; it uses three electric organs. The shock is used for defense and predation,” said Carlos David de Santana, an associate researcher at the U.S. National Museum of Natural History and first author of the article.
Biologists discovered one species of electric eel, Electrophorus electricus, should really be classified as three, based on environmental data, morphology, discharge voltage and the creatures’ DNA. The new species added to the genus are E. varii and E. voltaic.
“We used voltage as the key differentiation criterion. This has never been done before to identify a new species,” said Naércio Menezes, professor at the University of São Paulo’s Zoology Museum and principal investigator.
The E. voltai, named after Italian physicist Alessandro Volta, was recorded having a discharge of 860 volts. The previous strongest shock registered at 650 volts.
Santana said the discharge from the eels may be enough to stun a human, but unlikely to kill as the discharge consists of high voltage but low amperage, about 1 amp. In comparison, a power outlet can be as high as 10 or 20 amps, enough to kill to a person with prolonged contact.
“The shock stuns the victim. It’s sufficiently strong to help the fish capture prey or scare off a predator,” Santana said.
In their research, the biologists discovered that electric eels are not solitary creatures as was once believed. The eels frequently group up in adulthood to electrocute potential threats that could harm them.
Santana said the discovery of the new species is “suggestive of the vast amount of species that remain to be discovered in nature.”
“Furthermore, the region is of great interest to other scientific fields, such as medicine and biotechnology, reinforcing the need to protect and conserve it, and is important for studies involving partnerships among Brazilian researchers, and between us and groups in other countries, to explore the region’s biodiversity,” Santana said.
Other research groups are currently studying the enzymes produced by the eels’ electric organs to determine their usefulness in treating Alzheimer’s disease and other neurodegenerative disorders.