Taxonomic and distributional information need to be constantly updated as federal, state, and local agencies continue to use aquatic macroinvertebrates as biological indicators of water quality. While processing benthic macroinvertebrate samples provided by federal and state agencies, production taxonomists at EcoAnalysts, Inc. encountered larvae and pupae of the Neotropical chironomid Oliveiriella Wiedenbrug and Fittkau (Orthocladiinae) and Onconeura semifimbriata (Sæther) (Orthocladiinae) from sites in New Mexico and Arizona, USA. These occurrences represent the first Nearctic records of Oliveiriella, establishing a New World distribution, and expand the Nearctic range of Onconeura semifimbriata. We also identified larvae of Tempisquitoneura merrillorum Epler (Orthocladiinae) from 1 site in Nevada, 1 site in Utah, and 6 sites in Arizona, USA. These records expand the Nearctic range for T. merrillorum. These genera are very similar in appearance to other commonly encountered Orthocladiinae genera, but only the larva of Tempisquitoneura is included in a current taxonomic key for North America.