Planothidium minutissimum (Krasske) Lange-Bert. Planothidium minutissimum (Krasske) Lange-Bert. in Iconogr. Diatomol. 6: 278. 19991is new combination for Achnanthes lanceolata var. minutissima Krasske1. (Basionym:) fig. 18-22