Compare Pinnularia turgidula
Pinnularia acrospheria has more linear valves, lacking undulate margins.
Pinnularia acrospheria, P. turgidula, and varieties are distinguished from other Pinnularia by their relatively wide valves and externally mottled axial areas.
LM scalebar = 10 µm
Length Range
48-90 µm
48-90 µm
Width Range
12-15 µm
12-15 µm
Striae in 10 µm
11-12
11-12
Length Range
52.7-82.9 µm
52.7-82.9 µm
Width Range
9.7-12.0 µm
9.7-12.0 µm
Striae in 10 µm
11-13
11-13
