Adult butterflies have compound eyes with as many as 6000 different lenses, which are ideal for detecting movement. Caterpillars have around twelve ocelli and no compound eyes. Adult butterflies have a sucking mouthpart called a proboscis to aid in nutrient uptake. The butterfly's thorax contains the legs and wings. Butterflies have three pairs of legs, two of which may be smaller and held close to the body, called brush-feet.
Legs are functional for sense as well as movement, and contain sensory cells to locate host plants.
The veination is used in classi- fication. The fore and hind wings are linked together, allowing for powerful flight and energy conservation. Finally, the abdomen of a butterfly contains the digestive system, the heart, and the reproduc- tive organs. Life Cycle Butterflies are rather famous for their complex life cycle. The first stage is the egg, which may vary greatly in size and shape.