Naso unicornis

The bluespine unicornfish or short-nose unicornfish (Naso unicornis) is a tang from the Indo-Pacific. It occasionally makes its way into the aquarium trade. It grows to a size of 70 cm in length.
The bluespine unicornfish has a blueish-gray body with two blue spines on each side at the base of the tail and a short rostrum or bony horn on the forehead. In small fish the horn is missing and males additionally have tail streamers. These fish have a leather like skin instead of scales. The Bluespine Unicorn fish can grow up to 27 inches with the largest one caught to be 12.7 lbs.