According to the folklore of the Choctaw, a Native American people, Nalusa Falaya (literally "long black being" or "long dark creature") is a spirit in the form of a living shadow that inhabits the swamps and forests of what is now the southeastern United States. It resembles a human being, but its face is shrivelled, its eyes are very small, and its ears and nose are unusually long and pointed. According to traditional belief, Nalusa Falaya silently glides along the ground at night like a snake, stalking hunters. Mimicking human voices, it lures people deep into the woods, creeps up on them, and frightens them into unconsciousness. The spirit then pricks its helpless victim with a small thorn or spine, passing on its destructive power. Such a wound was believed to infect a person with an irresistible urge to commit evil deeds.

However, Nalusa Falaya does not always act as an evil spirit. In one legend, for example, it saves a hunter.

The Choctaw also told that Nalusa Falaya had many children who possessed an unusual ability while still young: at night, they removed the entrails from their bodies and, freed from their weight, transformed into small glowing or fiery orbs. Such lights could often be seen along the edges of swamps.