I’m tentatively placing these in the genus Orthezia. They’re tiny bright white creatures that I see sometimes on the underside of leaves. Photos of similar animals in iNaturalist are identified as Orthezia.
8/11/2023 On the underside of Prairie Coreopsis (Coreopsis palmata)
7/21/2018 On Brown-eyed Susan (Rudbeckia triloba)
7/21/2018