Achnanthidium contrarea (Lange-Bert. & Steindorf) Lange-Bert. Achnanthidium contrarea (Lange-Bert. & Steindorf) Lange-Bert. in Iconogr. Diatomol. 6: 271. 19991is new combination for Achnanthes contrarea Lange-Bert. & Steindorf1. (Basionym:) fig. 5: 1-19