The insect’s imago, or adult with wings, is its reproductive stage. Scales, each resulting from a single epidermal cell, cover the surface of both butterflies and moths. The two large compound eyes dominate the small head. These can tell the shapes and motion of flowers apart, but they can’t see far away objects clearly. Some species, especially those in the blue/violet range, have good color perception.

In contrast to moths, which have antennae that are tapering or feathery, the antennae are made up of many segments and have tips that are clubbed. Odours can be detected by the sensory receptors, which are concentrated in the tips. The palps and the feet contain taste receptors. The mandibles are usually small or absent, and the mouthparts are designed for sucking.

The first maxilla is elongated into a tubular proboscis that is curled up when the animal is resting and expanded when it is hungry. Palps serve as sensory organs on the first and second maxillae. Some species lack a maxillary or proboscis and do not feed as adults.

The gut and genital organs are located in the ten-segment abdomen. The terminal segment has been altered for reproduction, and the front eight segments have spiracles. A tubular structure is extruded and inserted into the female’s vagina during copulation, and the male has a pair of clasping organs attached to a ring structure. After the female is given a spermatophore, the sperm move to a seminal receptacle, where they are kept for later use. In the two genders, the genitalia are enhanced with different spines, teeth, scales and fibers, which act to keep the butterfly from mating with a bug of another species.