Nesting architecture of X. nasalis; Dissected nests of X. nasalis revealing the nest structure inside the bamboo culm and its residents. Measurements of the nest parameters are shown in Table 1. The diameters of the nests (excluding the nest thickness) were measured at the nest entrance, followed by the vestibulum (antechamber) length, cell length, and the inner most cell length, respectively (2a). Cells containing larvae with pollen masses and their feces were collected and weighted (2b).