It is carved & painted in the bluffs above the river near St. Louis
Personally, I am not convinced it is of American Indian origin
No but, here it is.
Nor am I. It looks more like a medieval European drawing of a mythical beast.
There was much more traffic between Europe and North America before Columbus, and even before the Vikings, than most people realize.
The “legend of the piasa” with the paisa stealing young women from the indian villages and carrying them off to its cave like a European dragon ... the indian hero finding a chink in its armor and serving himself up as bait while his warriors take their shots at the spot, is not American indian at all, it comes from a very white writer who made it up for a magazine in the 1830s as fiction. The wings did not appear in recreations of the piasa until after his story, in which the ability to fly plays a part.
There were indeed American indian paintings of horned cougars with monster or semi-human faces and serpent tails or bodies on the bluffs that were reported by trappers and explorers and also much earlier by French explorer Marquette. They do appear in engraved shell and pottery from Mississippian times.
But none of the river explorer’s descriptions had wings, certainly not poorly rendered bat or dragon wings. The modrn paintings that have been done on the bluffs in the last century are based more on the fictional children’s tale than on Marquette or historical record. The originals would be more catlike.
The original were vastly different, and the originals really were not that big- Marquette described the painting as being about the size of a calf. The purpose of the piasa paintings was probably to warn travelers of a naturally dangerous spot on the river. The Alton piasa was probably just an uktena, the underwater panther of eastern and southeastern indian lore that lives in whirlpools.
Here’s a very good history and explanation of the legend and towards the middle of the page is a more likely rendition of what was there from indian engravings on shell cups :
http://lithiccastinglab.com/gallery-pages/2013januarypiasapage1.htm