Special thanks for the pictures to Ole Johan Brett from Norway.
Ecsenius tricolor occurs in coral rich habitats at 10 m depth, here usually among Acropora branches.
Herbivory, feeds on algae and weeds.
The blenny has a striking blue-and-white line underneath the eye, which moves on the shoulder and changes above the anus into blue dots.
The body in the front area has a dark gray, the rear part of the animal has a bright yellow to orange tone.
The head is of a deep blue.