Chiton olivaceus

Chiton olivaceus can reach a length of 32–40 millimetres (1.3–1.6 in) and a width of about 16 millimetres (0.63 in). These large chitons have carinate plates with strongs ribs. The shell is oblong and oval. In the front and rear plates ribs have a radial pattern. The intermediate valves show a sharp beak and rounded sutural plates. Colors are very variable, ranging from olive-gray (hence the common name) to yellow-brown, sometimes black, orange, red or yellow. The girdle surrounding all of the valves is quite large and covered by bristles and scales.[3][4][5]

The teeth of these grazers of algae [6] are composed of magnetite, the hardest material usable by a living being.

This species is common in the Mediterranean sea around Italy and Greece, but can also to be found in the nearby Atlantic Ocean.[7]

Chiton olivaceus occur on a solid substrate, particularly stones and rocks, in the zones of sweeping of the waves, at a low depth.[3]