The Crown of Thorns sea star (Acanthaster pianci) is best known for its voracious appetite for coral. Its venomous spines can cause painful swelling. One of its few predators is the Triton�s Trumpet (Charonia tritonis), shown here as it is just beginning to attack the sea star. The early Hawaiian�s used the Triton�s Trumpet as a blowing shell.

These two were photographed in about 35 feet of water off the south Kohala Coast near Puako Beach on the Big Island of Hawaii.