What insect is known for producing silk?

The insect known for producing silk is the silkworm, the larva of the domestic silk moth Bombyx mori.

A silkworm spins a protective cocoon from a continuous strand of fibroin, a strong protein coated with sericin. The thread can be hundreds of metres long, making the larva exceptionally important to sericulture—the breeding and raising of silk moths for raw silk. Silkworms mainly eat white mulberry leaves.

Silk production began in China at least 5,000 years ago and eventually spread across Asia and into Europe. Chinese tradition credits the discovery of silk to the legendary empress Leizu. The domestic silk moth has been selectively bred for so long that it cannot fly effectively and depends on humans for reproduction.

The main terminology trap is that “silkworm” is not an adult worm and is not even a true worm: it is a caterpillar, or moth larva. The adult is a pale, flightless silk moth. Spiders also produce silk, but they are arachnids rather than insects and use their silk mainly for webs, egg sacs, and hunting structures.