Tseplik, N., Glushchenko, A. and Kulikovskiy, M. 2026. Achnanthidium stelleri sp. nov. (Achnanthidiaceae, Bacillariophyceae)—a new species from the A. pyrenaicum morphological group. Phytotaxa. 780, 3 (Oct. 2026), 285–293. DOI:https://doi.org/10.11646/phytotaxa.780.3.7.