Achnanthidium pirogueanum (G.Moser, Steindorf & Lange-Bert.) Lange-Bert. Achnanthidium pirogueanum (G.Moser, Steindorf & Lange-Bert.) Lange-Bert. in Iconogr. Diatomol. 6: 273. 1999is new combination for Achnanthes pirogueana G.Moser, Steindorf & Lange-Bert.