Drosophila melanogaster
The compound eye of the fruit fly contains 760 units or ommatidia, and are one of the most advanced among insects. Each ommatidium contains eight photoreceptor cells (R1–8), support cells, pigment cells, and a cornea (lens). Wild-type flies have reddish pigment cells, which serve to absorb excess blue light so the fly is not blinded by ambient light.