Histological structure of tripartite mushroom bodies in ground beetles (Insecta, Coleoptera: Carabidae)

Contrary to members of the suborder Polyphaga, ground beetles have been found to possess tripartite mushroom bodies, which are poorly developed in members of basal taxa and maximally elaborated in evolutionarily advanced groups. Nevertheless, they do not reach the developmental stage, which has been previously found in particular families of beetles. It has been pointed out that a new formation of the Kenyon cells occurs during at least the first months of adult life, and inactive neuroblasts are found even in one-year-old beetles. It has been suggested that there is a relation between the Kenyon cell number and development of the centers of Kenyon cell new-formation.