On rainy nights, Australia's Mount Kaputar is full of giant, fluorescent pink slugs or Triboniophorus aff. graeffei. The slugs can be up to 8 inches (20 centimeters) long and are hard to spot during the day when they hide in leaf mold. At night, the slugs come out to feed on moss. Some 17 million years ago, a volcano at Mount Kaputar erupted keeping the region damp enough for these slugs.