The nearly 300 species of snake found in Colombia represent nine of the eighteen families. Six families (Aniliidae, Boidae, Colubridae, Elapidae, Tropidophiidae, Viperidae) are within the infraorder Alethinophidia (advanced snakes) and three families (Anomalepididae, Leptotyphlopidae, Typhlopidae) are within the infraorder Scolecophidia (blind snakes). The largest snake ever known, Titanoboa, was discovered as a fossil in northeastern Colombia.