Tennessee has become the eighth state in America to record non-native Northern snakeheads in its waters.
According to a report from the Fayette Country Review, the Tennessee Wildlife Resources Agency's Fisheries Division received a report that a snakehead-like fish had been found by an angler in Poplar Tree Lake in the Meeman-Shelby State Park near Memphis.
Experts initially believed that the fish might be a Bowfin, Amia calva, a native to North America, but further analysis of the 16" long corpse which was found floating on the Lake, revealed it was a Northern snakehead, Channa argus.
Snakeheads were sold have been sold in the food trade and in the aquarium industry in the US in the past, but it is now no longer legal to trade in the species because it is considered a potential environmental threat.
Channa argus, which can reach over a metre in length and is a voracious predator with powerful and toothy jaws, is native to Asia and can tolerate cooler water than many other snakehead species.
TWRA Assistant Chief of Fisheries Bobby Wilson told the Fayette Country Review: "I hope that this was a case where this fish was someone's pet and it outgrew its tank and rather than killing it, they decided to let it go.
"Aquatic pet owners need to know that not only releasing fish and other exotic aquatic animals into the wild is illegal, it can also be detrimental to native fish populations as well.
"We already have a severe problem with other aquatic invasive species such as zebra mussels and Asian carp. We don't need snakeheads to add to the problem."
While the aquarium trade is frequently blamed for illegal introductions of Channa argus, the fish is rarely kept in aquaria. Many US fishkeepers oppose the ban on keeping the fishes.
In October 2004 snakeheads found in US waters were found on sale at a Korean food importer who was illegally bringing live snakeheads into the US for sale as food. The trade in live snakeheads has been banned in the US since 2002.
Channa argus is also banned in the UK under the Prohibition of Keeping or Release of Live Fish (Specified Species) Order in 1998.