Compare Pinnularia subgibba
Pinnularia gibba has capitate ends and wider axial area.
Pinnularia macilenta has broader, more lanceolate valves and less distinct broadly rounded to cuneate apices.
Pinnularia pseudogibba is more lanceolate and smaller.
Pinnularia subbgibba var. undulata has weakly triundulate sides and a more distinct fascia.
Pinnularia subgibba var. sublinearis has a more linear outline, with parallel sides.
Pinnularia parvulissima is smaller, with a consistently broad fascia.
LM scalebar = 10 µm
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
Length Range
71-124 µm
71-124 µm
Width Range
14-16.5 µm
14-16.5 µm
Striae in 10 µm
7-9
7-9
Length Range
40-88 µm
40-88 µm
Width Range
9-12 µm
9-12 µm
Striae in 10 µm
9-10
9-10
Length Range
67-83 µm
67-83 µm
Width Range
8.30-9.30 µm
8.30-9.30 µm
Striae in 10 µm
9-10
9-10
Also compare to
Pinnularia gibba
BioData Reference
Krammer 2000 Pl 68 Fig 1-8 Pl 69 Fig 1-5
Pinnularia
BioData Reference
Krammer 1992 Pl 48 Fig 8-14