Bristle Worm, Hermodice carunculata One of the most ferocious (relative to its size) animals on the reef, this predatory polychaete attacks sea anemones 10 times its size. Also called the fireworm, it has long, brittle, venomous bristles, which are harmful to touch. It grows to a foot long, feeding on coral and other sedentary animals by secreting digestive juices on them and then sucking up the frothy meal.