What specialized substance do females of the Family Colletidae secrete to line brood cells?

Answer

A specialized substance often described as cellophane-like

The Family Colletidae, which encompasses the Yellow-faced Bees, possesses a highly distinctive trait related to nesting behavior. The female bee secretes a specialized substance directly from her mouth during nest preparation. This secretion is often described using tactile comparisons, specifically as being cellophane-like in texture and property. The primary purpose of applying this lining to the interior of the brood cells and using it to plug the nest entrance is to create a barrier that is highly waterproof and resistant to contaminants, thereby ensuring a secure and protected environment necessary for the proper development of the brood offspring inside the cell.

What specialized substance do females of the Family Colletidae secrete to line brood cells?
insectbeeclassification