(Grunow) Nakov, Guillory, M.L.Julius, E.C.Ther. and A.J.Alverson 2015
Credit: Kalina Manoylov
Valves small
Valve face colliculate
Valve face tangentially undulate
Striae vary in length
Valves are small, with a colliculate and tangentially undulate valve face. The ornamentation of the central area varies from star-shaped to irregular. Striae vary in length.