Recent aquatic Hemiptera collections have yielded 15 new state records distributed among four midwestern States. These records include two species of water boatmen (Palmacorixa gillettei and Sigara mathesoni) new for Indiana, four water boatmen species (Cenocorixa utahensis, Corisella inscripta, Hesperocorixa laevigata, S. decorata), including one genus (Cenocorixa) new for Michigan, four water boatmen species (Corisella edulis, Trichocorixa macroceps, S. decoratella, S. mathesoni) and one backswimmer species (Notonecta indica) new for Ohio, and four water boatmen species (H. kennicotti, H. semilucida, S. compressoidea, S. variabilis) new for Pennsylvania.