This consists of a radial entrance tunnel leading to branched tunnels. These usually lie predominantly in one horizontal plane, but may extend into three dimensions. They lack enlarged brood chambers. Many gallery systems are often started in a small area of the tree. Unlike many xyleborines, the galleries of different individuals often interconnect so that beetles can move between galleries (Beeson 1961, Kasson et al. 2016).
Recent studies suggest that all the species in Ambrosiodmus and Ambrosiophilus Hulcr and Cognato are associated with a single species of polypore basidiomycete ambrosia fungus (Flavodon ambrosius) (Kasson et al. 2016; Li et al. 2017). This fungus has greater ability to break down lignocellulose than most ambrosia fungi. This enables the beetles to colonize wood at a more advanced state of decay than most ambrosia beetles, and to persist in the same tree over several generations (Kasson et al. 2016; Li et al. 2017).