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Halamphora oligotraphenta

(Lange-Bert.) Levkov 2009      Category: Asymmetrical biraphid
BASIONYM: Amphora oligotraphenta Lange-Bert. in Lange-Bert. and Metzeltin 1996
SYNONYM(S): Amphora veneta var. capitata  E.Y.Haw. 1974 

Halamphora normanii


Halamphora thumensis

LM scalebar = 10 µm = 80 pixels.


Contributor: Joshua Stepanek - March 2011
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


Valves are semi-lanceolate and strongly dorsiventral, with a smoothly arched dorsal margin and a weakly concave ventral margin. The ventral margin is often slightly tumid near the central portion. The valve ends are protracted and capitate. The raphe occurs near the ventral margin, is straight and gently deflects dorsally as it nears the central area. The proximal raphe ends are widely spaced; the distal ends are deflected dorsally. The axial area is narrow throughout. A dorsal and ventral fascia are both absent. Dorsal striae are punctate and radiate throughout. Ventral striae are continuous, although often difficult to observe in light microscope.

Original Description

Basionym: Amphora oligotraphenta
Author: Lange-Bert. in Lange-Bert. and Metzeltin 1996
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Stepanek, J. (2011). Halamphora oligotraphenta. In Diatoms of the United States. Retrieved May 25, 2018, from

Species: Halamphora oligotraphenta

Contributor: Joshua Stepanek

Reviewer: Sam Rushforth


Haworth, E.Y. (1974). Some problems of diatom taxonomy in Scottish lake sediments. Br. Phycol. J. 9: 47-55.

Lange-Bertalot, H. and Metzeltin, D. (1996). Indicators of oligotrophy - 800 taxa representative of three ecologically distinct lake types, Carbonate buffered - Oligodystrophic - Weakly buffered soft water. Lange-Bertalot, H. (ed.), Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 2. Ecology, Diversity, Taxonomy. Koeltz Scientific Books. Königstein, Germany, 2:390 pp.

Levkov, Z. (2009). Amphora sensu lato. In Diatoms of Europe, Volume 5. (H. Lange-Bertalot, ed). A.R.G. Gantner Verlag K.G. 916pp.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Halamphora oligotraphenta CAS

North American Diatom Ecological Database (NADED)


Autecology Discussion