Bombyx mori,the Silkworm Moth
The silkworm moth is actually an example of a fully domesticated insect. B. mori does not naturally occur in the wild and is completely dependent on humans for mating. Sericulture (silk production) has existed in China for at least 5,000 years, and thus far we have yet to produce synthetic silks capable of rivaling the real thing.
Silkworms feed predominantly on mulberry, most specifically white mulberry (Morus alba). The larvae feed voraciously, molting a total of four times, after which they will pupate in a cocoon of pure silk produced by their salivary glands. If the pupa were left undisturbed, at the end of its pupal stage it would produce enzymes that bore a hole into the silk, allowing the adult to emerge. The enzymes would reduce the silk length from nearly a mile down to a cluster loose strands, rendering the silk virtually useless.
Consequently, in the process of sericulture, the cocoon is often boiled, killing the pupa inside and making the silk easier to unravel. After the silk is fully unraveled and stretched to be turned into fabrics, the insect inside is often consumed in various cuisines.
B. mori, the domesticated silkworm is very closely related to B. mandarina, a wild-occurring bombycid whence B. mori speciated. The two, however, can still produce hybrid offspring. Unlike its undomesticated counterpart, B. mori has lost the ability to fly in its adult stage.
By all accounts, the silkworm moth owes its speciation to human influence and has virtually no ecological impact due to its domestication. It exists solely as a silk and food source.
All photos courtesy the Wikimedia Foundation.