A hiker in Florida found and took pictures of a rare rainbow snake, a species that experts say hasn't been seen in the area for more than 50 years.

Tracey Cauthen spotted the colourful, 4-foot-long snake while hiking in the Ocala National Forest, 47 miles north of Orlando, the FWC Fish and Wildlife Research Institute wrote on Facebook.

The Florida Museum of Natural History confirmed to the institute that this sighting was their first record of the species in Marion County since 1969.

The museum said rainbow snakes are nonvenomous and harmless.

"Rainbow snakes are highly-aquatic, spending most of their life hidden amongst aquatic vegetation; seldom seen, even by herpetologists, due to their cryptic habits," according to the institute.

Biologists speculate that the snake, also nicknamed the "eel moccasin," slithered its way into the forest after a recent change in water levels in the Rodman Reservoir.

The average adult Rainbow snake is around 3 feet 6 inches long with the record set at 5 feet 6 inches, according to the Florida Museum of Natural History.