Length of cells provisioned by Passaloecus areolatus and Passaloecus cuspidatus decreased as bore diameter increased, but volume of provisioned cells increased with increasing bore diameter. Activity of the parasitoid Omalus aneus increased length of provisioned cells. Wasp senescence did not result in increased cell length.
Fricke, John M.
"Factors Influencing Length and Volume of Cells Provisioned by Two Passaloecus Species (Hymemoptera: Sphecidae),"
The Great Lakes Entomologist, vol 25
Available at: https://scholar.valpo.edu/tgle/vol25/iss2/8