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This taxon is easily mistaken for smaller species of the Sellaphora pupula species complex, but is distinguished by characteristic hyaline areas on each side of the raphe. The largest valves in the size range are larger than most other Chamaepinnularia species in temperate waters of North America.

LM scalebar = 10 µm
Chamaepinnulaira witkowskii LM1 Chamaepinnularia witkowskii LM2 Chamaepinnularia witkowskii LM3 Chamaepinnularia witkowskii LM4 Chamaepinnularia witkowskii LM5
Length Range
13-19 µm
Width Range
4.5-5.5 µm
Striae in 10 µm
25-28

Also compare to

Chamaepinnularia krookii

BioData Reference
Lange-Bertalot and Genkal 1999 Pl 45 Fig 1-5