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Geissleria acceptata

(Hust.) Lange-Bert. and Metzeltin 1996      Category: Symmetrical biraphid
BASIONYM: Navicula acceptata Hust. 1950
SYNONYM(S): Navicula ignota var. acceptata (Hust.) Lange-Bert. in Krammer and Lange-Bert. 

Frustulia vulgaris


Geissleria decussis

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - May 2009
Length Range: 6-14 µm
Width Range: 3.4-5.2 µm
Striae in 10 µm: 12–18


Valves are elliptical with broadly rounded ends, 3.4-5.2 µm wide and 6-14 µm long. The raphe is straight and filiform. The axial area is narrow and linear. The central area is small, with an isolated stigma. Striae are uniseriate, radiate and number 12-18 in 10 µm. Areolae are apically elongated and number approximately 70 in 10 µm. Subpolar areolae, or annulae, are larger than areolae on other parts of the valve. The annulae form two rows at each pole. Internally, the annulae are surrounded by spherical nodules, typical of the genus Geissleria.

Original Description

Basionym: Navicula acceptata
Author: Hust. 1950
Length Range: 6–11 µm
Width Range: 3–5 µm
Striae in 10 µm: 16

Original Description

Schalen linear-elliptisch mit breit gerundeten, gewöhnlich sehr wenig und stumpf vorgezogenen Enden, 6-11 µ lang, 3-5 µ breit. Raphe gerade, fadenförmig, Axialarea sehr eng, linear, Zentralarea klein, gewöhnlich infolge Verkurzung der Mittelstreifeb etwas verbreitert. Transapikalstreifen kräftig, wenig radial bis fast senkrecht zur Mittellinie, etwa 16 in 10 µ, an den Enden etwas enger.

Original Images

Original text and images reproduced with permission by Schweizerbart.

Cite This Page:
Potapova, M. (2009). Geissleria acceptata. In Diatoms of the United States. Retrieved May 22, 2018, from

Species: Geissleria acceptata

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Hustedt, F. (1950). Die Diatomeenflora norddeutscher Seen mit besonderer Berücksichtigung des holsteinischen Seengebiets V-VII. Seen in Mecklenburg, Lauenburg und Nordostdeutschland. Archiv für Hydrobiologie 43:329-458, Tafs 21-41.

Krammer, K. and Lange-Bertalot, H. (1985). Naviculaceae Neue und wenig bekannte Taxa, neue Kombinationen und Synonyme sowie Bemerkungen zu einigen Gattungen. Bibliotheca Diatomologica 9:5-230, 43 pls.

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.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Geissleria acceptata CAS

North American Diatom Ecological Database (NADED)

NADED ID: 210001

Autecology Discussion

Fresh waters of moderate to high ionic strength

EMAP Assessment

The Environmental Protection Agency (EPA) western Environmental Monitoring and Assessment Program (EMAP) study was completed during the years 2000-2004 (see citations at bottom of this page). Over 1200 streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming) were selected for sampling based on a stratified randomized design. This type of design insures that ecological resources are sampled in proportion to their actual geographical presence. Stratified randomized design also allows for estimates of stream length with a known confidence in several “condition classes” (good or least-disturbed, intermediately-disturbed, and poor or most-disturbed) for biotic condition, chemistry and habitat.

EMAP Distribution

Geissleria acceptata

EMAP Response Plots

Geissleria acceptata

EMAP citations

Results are published in:

Johnson, T., Hermann, K., Spaulding, S., Beyea, B., Theel, C., Sada, R., Bollman, W., Bowman, J., Larsen, A., Vining, K., Ostermiller, J., Petersen, D. Hargett, E. and Zumberge, J. (2009). An ecological assessment of USEPA Region 8 streams and rivers. U.S. Environmental Protection Agency Region 8 Report, 178 p.

Stoddard, J. L., Peck, D. V., Olsen, A. R., Larsen, D. P., Van Sickle, J., Hawkins, C. P., Hughes, R. M., Whittier, T. R., Lomnicky, G. A., Herlihy, A. T., Kaufman, P. R., Peterson, S. A., Ringold, P. L., Paulsen, S. G., and Blair, R. (2005). Environmental Monitoring and Assessment Program (EMAP) western streams and rivers statistical summary. U.S. Environmental Protection Agency Report 620/R-05/006, 1,762 p.

Stoddard, J. L., Peck, D. V., Paulsen, S. G., Van Sickle, J., Hawkins, C. P., Herlihy, A. T., Hughes, R. M., Kaufman, P. R., Larsen, D. P., Lomnicky, G. A., Olsen, A. R., Peterson, S. A., Ringold, P. L., and Whittier, T. R. (2005). An ecological assessment of western streams and rivers. U.S. Environmental Protection Agency Report 620/R-05/005, 49 p.