Aphis elena Lagos-Kutz and Voegtlin, sp. nov. (Hemiptera: Aphididae), is described from specimens collected in Illinois, USA, on the North American native plant, Pycnanthemum virginianum (L.) T. Dur. & B.D. Jacks. ex B.L. Rob. & Fernald (Family: Lamiaceae). Both apterous and alate viviparae are described and illustrated, and a dichotomous key is provided to apterous and alate viviparae of the six species of Aphis that have been recorded on plants in the family Lamiaceae in North America. Neighbor-joining analysis of cytochrome oxidase 1 (Cox1) indicated a close relationship of the new species with Aphis monardae Oestlund, which also feeds on a member of Lamiaceae. The range of pair-wise distances for DNA barcoding of these species is 0.17–0.33%. The newly described Aphis elena is morphologically more similar to Aphis gossypii Glover than it is to Aphis monardae.
