Diatoms of North AmericaDiatoms of North America
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Compare Amphora bicapitata

M.H.Hohn and Hellerman 1966

Compare

Halamphora latecostata has a narrower axial area, less coarse dorsal striae and lacks a small internal siliceous plate at mid-valve. Halamphora acutiuscula has a narrower axial area and more uniform, less coarse, dorsal striae. Halamphora bullatoides is very similar in size, shape and dorsal stria density, but has longer, denser ventral striae and less punctate dorsal striae. Halamphora subtilis is much smaller.

LM scalebar = 10 µm
Halamphora bicapitata LM3 Halamphora bicapitata LM2 Halamphora bicapitata LM1 Halamphora bicapitata LM7 Halamphora bicapitata LM6 Halamphora bicapitata LM4 Halamphora bicapitata LM5
Length Range
23.9-29 µm
Width Range
5.2-5.5 µm
Striae in 10 µm
20-22 off-center on the dorsal side, 22-23 off-center on ventral side

Halamphora latecostata

Štěpánek and Kociolek 2013

Halamphora latecostata LM1 Halamphora latecostata LM6 Halamphora latecostata LM5 Halamphora latecostata LM7 Halamphora latecostata LM2 Halamphora latecostata LM3 Halamphora latecostata LM4
Length Range
16-50 µm
Width Range
4.1-7.9 µm
Striae in 10 µm
9-13 at dorsal center; 15-18 at dorsal apices; 19-20 ventral

Halamphora subtilis

Stepanek and Kociolek 2013

Halamphora subtilis LM2 Halamphora subtilis LM14 Halamphora subtilis LM13 Halamphora subtilis LM5 Halamphora subtilis LM1 Halamphora subtilis LM10 Halamphora subtilis LM17
Length Range
12.7-19.3 µm
Width Range
2.7-3.5 µm
Striae in 10 µm
20-25

Also compare to

Halamphora acutiuscula

(Kütz.) Levkov

Halamphora bullatoides

(M.H.Hohn and Hellerman) Levkov

Halamphora subtilis

Stepanek and Kociolek