Stoneflies are well known as indicators of water quality. Their presence in running waters, glacial meltwaters, and large oligotrophic lakes is rapidly declining the world over. In the USA, states partner with the U.S. Fish and Wildlife Service to protect habitat and wildlife through the development of State Wildlife Action Plans (SWAPs). Plants and wildlife species often enter these SWAPs as Species in Greatest Conservation Need (SGCN). Arkansas currently lists nine stonefly species as SGCNs and has funded research on them through SWAP grants. However, these nine species were initially chosen based on the small amount of data from a few papers. A more comprehensive assessment using museum specimen data is necessary to assess completeness of sampling, the relative rarity and endemicity of species, temporal changes in distribution, and the conservation status of species in Arkansas. Herein, we publish a data paper and preliminary dataset comprised of specimen data primarily from the Illinois Natural History Survey Insect Collection, Canadian National Collection, Western Kentucky University, P. N. Hogan Personal Collection, and from existing literature sources. These data are made publicly available by the Global Biodiversity Information Facility (GBIF) to allow for comprehensive assessment of the Arkansas Plecoptera assemblage. More recent occurrence data are needed to accurately assess imperilment of Arkansas stonefly species; these data will be provided through targeted collecting, collaboration with others in Arkansas, and through investigation of additional museum collections. This dataset includes > 3,500 specimen records (ethanol vials or pins with or without catalog numbers) and accounts for 84 stonefly species in Arkansas, six more species than indicated in published records. Perlidae contributed 29 of these species followed distantly by Perlodidae (15), Capniidae (14), Taeniopterygidae (9), Leuctridae (7), Chloroperlidae (5), Nemouridae (4), and Pteronarcyidae (1). A species accumulation curve predicts that sampling of species is nearly complete with a Chao1 estimate of 88.0 ± 3.7 species. Our data demonstrate that 25 species are known from ≤ five records, suggesting that many more than the nine recognized stonefly SGCNs in Arkansas may meet standards for inclusion.