The genus Samia is found in the sub tropical to tropical East. India across to China & south into Indonesia. Once thought to be one species with many forms it has been recently re classified into individual species. Saying that it is still a complex genus.
Samia cynthia was brought to Europe & the USA in a bid to start farming it's silk. All attempts failed however the livestock did escape & can still be found today in Italy & a few places in USA.
This moth has proved to be very adaptable & over wintering cocoons frost hardy.
Samia ricini is one of only two fully domesticated silk moth species & has been raised for silk production in North east India for hundreds of years maybe even thousands. This species is not found in the wild & is thought to be totally man made over many years of domestic breeding.