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Halamphora oligotraphenta is distinguished from H. veneta by having protraccted capitate valve ends, and from H. coffeaeformis by its punctate dorsal striae, and widely spaced proximal raphe ends.

LM scalebar = 10 µm
Halamphora oligotraphenta LM7 Halamphora oligotraphenta LM1 Halamphora oligotraphenta LM5 Halamphora oligotraphenta LM6 Halamphora oligotraphenta LM4 Halamphora oligotraphenta LM3 Halamphora oligotraphenta LM2
Length Range
22-33 µm
Width Range
3.9-4.6 µm
Striae in 10 µm
26-30 in the center, 32-34 near the poles

Halamphora veneta

(Kütz.) Levkov 2009

Halamphora veneta LM5 Halamphora veneta LM3 Halamphora veneta LM1 Halamphora veneta LM3 Halamphora veneta LM4 Halamphora veneta LM2
Length Range
10-40 µm
Width Range
3.5-6 µm
Striae in 10 µm
20-25 in central area, 27-30 at the ends

Halamphora coffeaeformis

(C.Agardh) Levkov 2009

Halamphora coffeaeformis LM3 Halamphora coffeaeformis LM6 Halamphora coffeaeformis LM1 Halamphora coffeaeformis LM5 Halamphora coffeaeformis LM7 Halamphora coffeaeformis LM4 Halamphora coffeaeformis LM2
Length Range
15-40 µm
Width Range
5-7 µm
Striae in 10 µm
17-21 at center, 22-24 near apices