The caved wyvern is, to the untrained eye, nothing more than a glorified snake. However, it is actually a Draco Familias (that's dragon to you and me), and in the sub-class Draco Wyvern (which, unsurprisingly, is a wyvern). Their scales are a lime green color, as are their teeth and eyes. They're venom is also green, and highly bio-acidic, death is a sure thing, with no known cure. Their fangs measure at an impressive half a foot, which are constantly being replaced. It has a bright red tongue, which is one feature that distinguishes it from snakes: The caved wyvern actually uses it's eyes, while the snake "sees" with it's tongue by use of the Jacobsons Organ.