The life histories of Acrosternum hilare and Cosmopepla bimaculata were studied in southern Illinois from May 1972 to September 1974 and from September 1992 to June 1995. Both species were bivoltine, overwintered as adults, and became active in early spring. The subsequent generations were characterized by marked overlapping of the nymphal instars. No active adults were found after early November.
McPherson, J. E. and Tecic, D. L.
"Notes on the Life Histories of Acrosternum Hilare and Cosmopepla Bimaculata (Heteroptera: Pentatomidae) in Southern Illinois,"
The Great Lakes Entomologist, vol 30
Available at: https://scholar.valpo.edu/tgle/vol30/iss2/2