Compare Pinnularia subgibba var. sublineairs
Pinnularia subgibba has expanded valve margins.
Pinnularia procera can be difficult to separate, however it has narrower valves, (occasionally) undulate margins, and a broader fascia.
Pinnularia laxa has narrower valves, a higher stria density, and a broader fascia.
Pinnularia delicata has capitate apices and narrower valves.
Pinnularia rivularia has a lower stria density and larger valves.
LM scalebar = 10 µm
Length Range
61-79 µm
61-79 µm
Width Range
9-10 µm
9-10 µm
Striae in 10 µm
9-10
9-10
Length Range
63-127 µm
63-127 µm
Width Range
11.7-13.6 µm
11.7-13.6 µm
Striae in 10 µm
8-9
8-9
