The Anatomy of a Butterfly

In all insects the body is divided into three parts - the head, the chest, (thorax), which carries the legs, and wings, and the abdomen, which carries the digestive and generative organs.

The h e a d includes two large, compound eyes which take up a lot of room. Each eye has many hundreds of small lenses, a fixed focus, and its surface sufficiently curved to give a wide field of vision. Its practical efficiency is excellent. Below the eyes is the proboscis, a minute pipe through which the insect can suck up water and liquid food. Butterfly does not have any jaws. On each side of the proboscis are the palpi, small, paired triple-jointed organs of variable size. On the top of the head between the eyes are two antennae, in butterflies more or less expanded at their apices into bulbous clubs. Each antenna is an important sensory organ, the shaft provided with short hairs, important receptors in the insect's sensory system, which warm of aerial vibrations indicating nearby noise and movement. The antennae also help to maintain balance during flight. A narrow neck connects the head with the chest (thorax) stoutly constructed with rigid plates of hardened chitin. It forms a firm base for three pairs of legs, two pairs of wings and their muscles. Each functional leg has thigh (femur), a shin (tibia) and five-joined foot (tarsus) ending in a pair of claws, but this structure varies in different species. In particular the front leg is always vestigial in the Fritillaries, Satyrids and their relatives. The wings are composed of a thin chitinous membrane supported by minute tubes known as veins. In almost all butterflies the wings are covered by scales, thousands of tiny, flat platelets, often beautifully grooved, lying in rows across the which they are fixed by peg-and-socked attachments. The scales are of two types. First are the cloaking scales which provide the wing-markings, usually by actual pigments, although the gleaming green and blue tones which are so striking (as for instance in the Common Blue) are produced by diffraction of light (interference colours). Secondly, in many but not at all species, there are specialised "scent scales" (androconia), present only in males, which are of many shapes but always quite unlike the cloaking scales. They are concerned with sexual attraction, probably through the secretion and dispersal of aphrodisiac or identifying scents (pheromones) to which the female will react.

Photo 1. Aporia crataegi L. on flower of Plantago media, 26. May. 1997, section N1, site Bene Hill-4, N48°.58' E22°45', Transcarpathia. Photo made by the author of this homepage.

Source: Higgins, L.G., Hargreaves, Br., The Butterflies of Britain an Europe. Collins, London, 1983, p. 11, 12.

Distribution map in SW Ukraine is available.

*ALEXANOR'S office information in Ukraine is available.

This page was created for "ALEXANOR" (Company for Scientific Implementation )

by S.G. Popov (Last update February 14 2009)

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