Faunistic studies of regional biodiversity of aquatic insects are increasing in importance as declines are noted globally. Federal and state government conservation attempts for rare and threatened species are predicated upon the initial research of specialized taxonomists and trained field biologists. Reporting of aquatic insect occurrence data provides a baseline for conservation agencies to compare water quality monitoring studies. Updated fieldwork, literature reviews, and database queries for stoneflies from the mid-Atlantic USA state of Maryland necessitated an assessment of species diversity for the state. Seven new state records and one new literature record are presented, bringing the total number of species to 122. Chao1 estimates of species richness are presented for diversity hotspots and the state as a whole, indicating that increased sampling is still necessary to fully understand diversity patterns. Accompanying are assessments of elevation trends and adult presence patterns within nine families. Collections are predominantly restricted to the Appalachian region, herein we direct future efforts to focus on understudied regions. An outline of distribution knowledge for species is presented to inform upcoming State Wildlife Action Plans.

Larval and adult stoneflies were collected by the authors during the 1990's and from 2020–2022. Collected individuals were preserved in 95% ethanol and stored in either Western Kentucky University or Phillip N. Hogan Collection. For each collection, GPS coordinates were taken at the site location. Literature data were compiled to supplement distribution knowledge. Coordinate pair data were identified for literature records using locality descriptions. All data have been formatted to match Darwin Core Archive standards. 

Maryland_collections_DwCA.csv

Occurrence dataset in a comma-separated text file.