Achnanthes fonticolanceolata Lange-Bert. & Schim. Achnanthes fonticolanceolata Lange-Bert. & Schim.is basionym for Planothidium fonticolanceolatum (Lange-Bert. & Schim.) Lange-Bert. in Iconogr. Diatomol. 6: 275. 199911. (Basionym:) fig. 88: 1-7