(M.H.Hohn and Hellerman) Lange-Bert. and Metzeltin 1996
Credit: Loren Bahls
Valves broadly linear
Apices obtusely rounded
Central striae widely spaced
Conopea narrow
Central area rectangular
Sellaphora alastos has large, broadly linear valves with obtusely rounded apices. The central striae are more widely spaced than more distal striae. The narrow axial and rectangular central areas are bordered by narrow conopea.