No lizard demons.
A demon is a real being, but it has no body. A demon is a fallen angel.
When we interact with lizards we see no facial expressions and feel no emotions from them. Therefore when we interact with demons, we associate the cold evil of them with lizards.
But demons and lizards are not related.
Dragon comes from the Greek drakon which is related to Sanskrit drnati
This is related to the English word tear.
In ancient times when we were hunters, the most dangerous beasts were the ones which would tear us apart. These strong fighters came to be called DRAKON. The most fearsome of these was the mammoth.
People who live near large reptiles like crocodiлес take the concept of a fearful beast who tears people apart, and associate it with the reptiles.