Achnanthes lanceolata var. robusta Hust. Achnanthes lanceolata var. robusta Hust.is replaced synonym for Planothidium robustius Lange-Bert. in Iconogr. Diatomol. 6: 279. 199911. (Syn. subst.:) fig. 13: 47-49 non Achnanthes delicata var. robusta Hustedt 1934