Compare Ulnaria contracta
Ulnaria contracta may be confused with larger specimens of Synedra goulardii; however, S. goulardii is more constricted at the center, less linear in outline, and tapers more gradually from the center to valve apices. Ulnaria ulna is greater in length than U. contracta and has broader, less constricted ends.
LM scalebar = 10 µm
Length Range
65-149 µm
65-149 µm
Width Range
6.5-6.8 µm
6.5-6.8 µm
Striae in 10 µm
10-12
10-12
Length Range
55-103 µm
55-103 µm
Width Range
8.5-10.5 at center; 8.6-12.4 at maximum µm
8.5-10.5 at center; 8.6-12.4 at maximum µm
Striae in 10 µm
9-12
9-12
