What characteristic, cellophane-like substance do female Hylaeus bees use when constructing nest cells?
A material secreted from glands used to line the cell walls before provisioning.
The nesting behavior of many *Hylaeus* species involves meticulous construction of individual cells within their chosen cavity. After securing a suitable location, such as a hollow reed or beetle burrow, the female bee secretes a unique substance from glands. This material is thin, resembles cellophane, and is used specifically to line the inner walls of each cell chamber. This delicate lining serves as a protective barrier for the developing larva and its food supply (the pollen-nectar provision) before the egg is laid. This particular nesting architecture, characterized by paper-thin walled chambers, is a feature shared by the entire family Colletidae, leading to the alternative common name 'cellophane bees' for this group.
