Contia tenuis

They have a specialized diet, feeding almost entirely on slugs and are therefore most common where slugs are in abundance. Being slug specialists, they are well equipped with unusually long, curved teeth for handling such prey. Because they are dependent upon different species of slugs, these snakes are comfortable in moist conditions and lower temperatures, even foraging in the rain. They are only found in areas where slugs are present. They are rare west of the Cascades, but are not absent.

A sharp spine-like tip at the end of the tail gives the snake its name but its exact purpose is not certain. When captured, they may press the tip against the captor, suggesting it may serve as a defensive mechanism. Others hold that it may be used as an aid in burrowing.