A bacteriocyte (Greek for bacteria cell), also called a mycetocyte, is a specialized adipocyte found in some insect groups such as aphids, tsetse flies, german cockroaches, and many others. Mycetocyte symbionts specifically include three insect groups: Cockroaches, Homoptera such as aphid, and Coleoptera such as weevils. These cells contain endosymbiotic bacteria such as Buchnera species, which provide essential amino acids and other chemicals to their host. Bacteriocytes are maternally-transmitted, i.e. the mother transmits her endosymbionts to her offspring. In some cases, the bacteria are transmitted in the egg, as in Buchnera[1]; in others like Wigglesworthia, they are transmitted via milk to the developing insect embryo.