Fig. 1

Schematic representation of H. illucens larval digestive tract. The digestive tract of this insect species is characterized by an extremely long midgut. This is divided into distinct regions characterized by specific physico-(bio)chemical conditions and digestive activities. Bonelli et al. 2019 [110] showed that each region of the midgut harbors distinct bacterial communities, suggesting a specific compartmentalization of microbial partners according to digestive processes. AMG, Anterior midgut; MMG, Middle midgut; PMG, Posterior midgut.