David C Houghton

Data for "An Analytical Synopsis of Caddisfly (Insecta: Trichoptera) Taxonomic History and Progress in Canada and the United States" Abstract: A total of 1,510 caddisfly species representing 28 families and 155 genera are reported from the 63 states and provinces of Canada and the United States of America (USA). These species have been described over a period of nearly 270 years, with the most prolific period occurring during the 1930–1940s. The families Hydroptilidae (307), Limnephilidae (255), and Hydropsychidae (159) contained the most species, whereas six families contained less than five species each. Canada and the USA host 644 and 1,487 species, respectively. The states with the greatest species richness were Tennessee (384), Virginia (383), and Alabama (378), and those with the least were Rhode Island (27), Prince Edward Island (23), and Nunavut (15). Differences in state species assemblages largely followed a geographic pattern, with a non-metric multidimensional scaling ordination suggesting six regions of caddisfly diversity corresponding to the Central, Far North, Northeastern, Northwestern, Southeastern, and Southwestern portions of the study area. Caddisfly species richness was highest in the Southeastern region, despite being the smallest region of the six, and lowest in the Far North. Species rarefaction predicted 129–181 species remain to be discovered within the two countries, while multiple linear regression modeling using common environmental variables suggested 17 states with at least 50 species still remaining to be found in each. File overview: This .xlsx file contains a presence-absence matrix of caddisfly species by state and province within Canada and the United States organized alphabetically by family, genus, and then specific epithet. A total of 1,510 species across 28 families and 155 genera are marked as present ("1") or absent ("0") for each of the 63 states and provinces. Data on species presence in states were sourced from the Nearctic Checklist by Rasmussen and Morse (2023), recent published literature, and our own unpublished datasets. State species records that were noted as dubious or erroneous in the Nearctic Checklist were marked as absent. Species considered nomina dubia were not included. Rasmussen, A.K., & Morse, J.C. 2023. Distributional Checklist of Nearctic Trichoptera (2022 Revision). Florida A&M University, Tallahassee. 541 pp.  [Available at http://www.Trichoptera.org]