Nautilus have up to 90 tentacles (without suckers) arranged in circles. They are the only living cephalopod with a shell. The shell uses countershading camouflage, which is darker on top and lighter on the bottom.
Nautilus are sometimes called "living fossils." The species has existed relatively unchanged for 500 million years.
The nautilus is a predator of shrimp and small fish. They are found only in the Indo-Pacific ocean on steep slopes of coral reefs.
