Abstract
A female spider wasp Dipogon variegatus was filmed stealing fragments of pollen-nectar provision from a solitary bee (Osmia cornuta) nest and using them for the construction of her nest. The female wasp applied the sticky fragments of the pollen-nectar provision to the outer surface of her closing nest plug, thus gluing together pieces of debris filling the nesting cavity. Previous descriptions of D. variegatus nests indicate that females of this species usually use spider silk to provide cohesion to the nest plug. Our observations provide an example of behavioural plasticity and innovation in the use of nesting materials. We describe the structure of the nest and the sequence of emergence of the progeny.