Voltinism in Merragata brunnea (Heteroptera: Gerromorpha: Hebridae) in southern Illinois

Voltinism in Merragata brunnea Drake was studied in southern Illinois during 1989 and 1990. This species overwintered as adults, which became active in early March. First instars were found from mid-May through mid-September, second instars from mid-May through mid-October, third instars from early June through mid-October, fourth instars from late May through early November, fifth instars from late May through late October, and adults from early March through mid-November. The sequences of peaks of nymphal instars and adults indicate that this species is bi- or trivoltine in southern Illinois.