silkworm

Despite its name, the silkworm is in fact the larva of a moth. Various species of the moth families Bombycidae and Saturniidae spin silken cocoons in which to pupate but the Chinese silkworm moth produces so much that it has been the basis of the eastern silk cloth industry for at least 2,000 years. Traditionally, the larvae are fed on white mulberry leaves.

Usually the larva of the common silkworm moth Bombyx mori. After hatching from the egg and maturing on the leaves of white mulberry trees (or a synthetic substitute), it spins a protective cocoon of fine silk thread 275 m/900 ft long. To keep the thread intact, the moth is killed before emerging from the cocoon, and several threads are combined to form the commercial silk thread woven into textiles.

Other moths produce different fibres, such as tussah from Antheraea mylitta. The raising of silkworms is called sericulture and began in China in about 2000 BC. Chromosome engineering and artificial selection practised in Japan have led to the development of different types of silkworm for different fibres.