Brachysira Styriac Guide
Credit: Loren Bahls
  1. Valves lanceolate
  2. Central area elongate and constricted in larger valves
  3. Apices not protracted

Valves are lanceolate with unprotracted apices. The central area is apically elongate, with a median constriction, a feature most pronounced in the largest valves. Striae number 26-30 in 10 µm.