Kerriidae is a family of scale insects, commonly known as lac insects or lac scales. Some members of the genera Metatachardia, Tachardiella, Austrotacharidia, Afrotachardina, Tachardina, and Kerria are raised for commercial purposes, though the most commonly cultivated species is Kerria lacca. These insects secrete a waxy resin that is harvested and converted commercially into lac and shellac, used in various dyes, cosmetics, food glazes, wood finishing varnishes and polishes.[citation needed]