So that thing isn't the serpent at all.
The tempting Serpent is depicted as a bipedal salamander-like creature because it was assumed that the serpent could walk before God's curse compelled it to crawl and eat dust. The human-headed Serpent was introduced into art in the late 13th century. Subsequent Renaissance artists generally abandoned the depiction of Serpent as a human-headed creature.
The snake has a head with thick blond hair, much idealised.