I feel like I've seen the Picnic Bug on Fraggle Rock. Was he ever on Fraggle Rock? He reminds me of one of the background cave creatures. I know the Sneels were on Fraggle Rock, but was the Picnic Bug?
The same puppet, though slightly different in design, also appears in Song of the Cloud Forest, in a big crowd shot during "Munching Forest". So the puppet does exist before the Dr. Seuss show. But the origin? I don't know, but I don't recall seeing it of Fraggle Rock. (Also note that a Rumble Bug appears right next to it during the "Forest" song, too, so one can see the differences in the two.)