Compare Cocconeis cascadensis
Compare
Cocconeis placentula has much finer areolae and striae on the rapheless valve and the raphe valve has a smooth submarginal hyaline area.
Cocconeis disculus also has large coarse areolae on the rapheless valve, but the raphe valve has a smooth submarginal hyaline area. Cocconeis disculus has not yet been confirmed in streams and rivers of California.
LM scalebar = 10 µm
Length Range
15.7-40 µm
15.7-40 µm
Width Range
8.7-22 µm
8.7-22 µm
Striae in 10 µm
Raphe valve 15-18.5, rapheless valve 7–12
Raphe valve 15-18.5, rapheless valve 7–12
Cocconeis placentula sensu lato
Length Range
9-68 µm
9-68 µm
Width Range
7-32 µm
7-32 µm
Striae in 10 µm
20-24 on raphe valve, 15-25 on rapheless valve
20-24 on raphe valve, 15-25 on rapheless valve
Cocconeis coreana
Length Range
21-58 µm
21-58 µm
Width Range
11.5-36.6 µm
11.5-36.6 µm
Striae in 10 µm
18-24 raphe valve, 18-24 rapheless valve
18-24 raphe valve, 18-24 rapheless valve
Cocconeis czarneckii
Length Range
17.7-51 µm
17.7-51 µm
Width Range
11.3-37.9 µm
11.3-37.9 µm
Striae in 10 µm
Raphe valve 18-30, rapheless valve 20-26
Raphe valve 18-30, rapheless valve 20-26
Also compare to
Cocconeis disculus
BioData Reference
Krammer and Lange-Bertalot 2/4 PL 56 Fig1-13