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Navicula geronimensis

Potapova in Potapova and Charles 2004      Category: Symmetrical biraphid

Navicula germainii


Navicula goersii

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - February 2011
Length Range: 46-50 µm
Width Range: 8-9 µm
Striae in 10 µm: 9-10


Valves are linear-lanceolate. Axial area is narrow. Central area is strongly asymmetrical, wedge-shaped and bordered by irregularly shortened striae at the primary side and semi-lunate in shape on the secondary side. Raphe is almost straight, but slightly shifted towards primary side near the central valve. Proximal raphe ends are slightly expanded and sharply deflected towards the primary side. Terminal raphe fissures are deflected toward the primary side and bifurcate at the valve apices. Striae are radiate in the central part of the valve and parallel near apices. Striae are 9-10 in 10 µm. Areolae are lineolate and number approximately 24-26 in 10 µm.

Original Description

Author: Potapova in Potapova and Charles 2004
Length Range: 46-50 µm
Width Range: 8-9 µm
Striae in 10 µm: 9-10

Original Description

Valves linear-lanceolate, 46-50 µm long, 8-9 µm wide. Raphe almost straight, but near the center slightly bent towards primary side of the valve. Central raphe endings slightly expanded and sharply bent towards primary side. Terminal fissures deflected towards primary side and bifurcate over valve apices. Striae radiate at the middle part of the valve, but parallel near apices, 9-10 in 10 µm. Areolae apically elongate, about 24-26 in 10 µm. Axial area narrow. Central area asymmetrical, bordered by irregularly shortened striae at the primary side, and semi-lunate at the secondary side.

Original Images

Cite This Page:
Potapova, M. (2011). Navicula geronimensis. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Navicula geronimensis

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Potapova, M. and Charles, D.F. (2004). Potential use of rare diatoms as environmental indicators in U.S.A. rivers. In: M. Poulin (ed.), Proceedings of the Seventeenth International Diatom Symposium, Ottawa, Canada, 25th-31st August 2002. Biopress Limited, Bristol, U.K. pp. 281-295.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Navicula geronimensis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 46254

Autecology Discussion