Cerastes

From publisher blurb: A cerastes is a type of gigantic carnivorous earthworm. They live in any areas providing earth or sand loose enough for them to move about in. For worms, they are remarkably intelligent and can be tamed to a certain extent. Untamed cerastes are extremely dangerous if the horn-like protrusions on the top of their heads are touched in any way. They react instinctively to attack anything that touches their heads.