What does an immature mayfly look like?

An immature mayfly, known as a nymph, typically has a long, slender body with a flattened shape, and is often brown or green for camouflage in aquatic environments. They possess several pairs of gills along their abdomen, which aid in respiration, and have a set of three long tails extending from the rear. Mayfly nymphs also have large, compound eyes and can vary in size, usually measuring a few millimeters to several centimeters long, depending on the species.