Lepidoptera (/ˌlɛpɪˈdɒptərə/ LEP-ih-DOP-tər-ə) or lepidopterans are an order of winged insects which include butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organisms, making it the second largest insect order (behind Coleoptera) with 126 families and 46 superfamilies, and one of the most widespread and widely recognizable insect orders in the world.
Lepidopterans have several distinctive features, especially coloured scales that cover their bodies, large triangular wings, and a proboscis for drinking nectar. Almost all species have membranous wings. Mating and egg-laying are normally near or on host plants for the larvae. Butterflies and moths undergo complete metamorphosis. The larva is called a caterpillar; it has a cylindrical body with a well-developed head, chewing mouthparts, three pairs of legs and up to five pairs of prolegs. As it grows, it changes in appearance, going through a series of stages called instars. Once mature, it develops into a pupa. A few butterflies and many moth species spin a silk casing or cocoon for protection prior to pupating, while others just go underground. A butterfly pupa, called a chrysalis, has a hard skin, usually with no cocoon. In the pupa, metamorphosis occurs, and a sexually mature adult emerges.
