Popolopoï are a species of butterfly found commonly in the Glade of Dreams. Most popolopoï are bright blue; yellow popolopoï are rarer. For the majority of the Rayman series, popolopoï act merely as background elements are are not mentioned or named; however, they are given much more prominence in Rayman M.
Another species of butterfly found in the Rayman series are the tribelles. It is unknown if there is any connection between the tribelles and the popolopoï, or if either species of butterfly have any connection to the shadowy caterpillars encountered throughout the series.
In the original Rayman game, blue popolopoï can be seen fluttering amidst the scenery of the Dream Forest. In the Sega Saturn and Atari Jaguar versions, several other colours are included; these colours reappear in Rayman Junior and Rayman Designer, which also introduces a flashing, multicoloured variety.
In Rayman 2: The Great Escape and its remakes, blue and yellow popolopoï can be seen in the background in the Woods of Light. Rayman 2's credits give a special thanks to someone called ‘Popolopoy’, providing a likely inspiration for the name given to them in Rayman M. Incidentally, the credits also give special thanks to the ‘T-Trouble Team’.
In Rayman M, there is an entire racing mode which revolves around them. In Popolopoï Mode, the player must run through the race course while shooting as many popolopoï as he can; each popolopoï struck grants the player extra time, which he will need in order to finish the race. The yellow popolopoï are rarer and grant more time than the blue ones.
In Rayman 3: Hoodlum Havoc, sparkling blue popolopoï are visible in the Fairy Council. Appearing randomly, they twirl around Rayman while making slight twinkling noises. Both the blue and yellow types appear in the Game Boy Advance version.
Popolopoï will appear in the upcoming Rayman Origins. They can be seen fluttering around in one level shown in the game's trailer, and some of them can be seen flying away from the stone circle right before Rayman is created.