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Navicymbula pusilla

(Grunow in A.Schmidt) Krammer 2003      Category: Asymmetrical biraphid
BASIONYM: Cymbella pusilla Grunow in Schmidt et al. 1875
SYNONYM(S): Navicella pusilla (Grunow) Krammer | Seminavis pusilla (Grunow) E.J.Cox and G.Reid 

Navicula winona


Neidiomorpha binodiformis

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - October 2011
Length Range: 16-33 µm
Width Range: 4.2-5.9 µm
Striae in 10 µm: 16-18 in the center valve, 19-20 at the ends


Valves are moderately dorsiventral with an arched dorsal margin and flat, or slightly convex, ventral margin. The apices are not protracted. The axial area is narrow and widens in the valve center to form a small, lanceolate central area. The raphe is straight and weakly lateral, with external proximal ends and terminal fissures hooked to the dorsal side. Striae are radiate in the valve center, becoming convergent at the ends. Areolae are apically elongated and number 45-55 in 10 μm.

Original Description

Basionym: Cymbella pusilla
Author: Grunow in Schmidt et al. 1875
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Potapova, M. (2011). Navicymbula pusilla. In Diatoms of the United States. Retrieved May 24, 2018, from

Species: Navicymbula pusilla

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Cox, E.J. and Reid, G. (2004). Generic relationships within the Naviculineae: a preliminary cladistic analysis. M. Poulin (ed.), Proceedings of the Seventeenth International Diatom Symposium, Ottawa, Canada, 25th-31st August 2002. Biopress Limited, Bristol, U.K. pp. 49-62.

Krammer, K. (1997). Die cymbelloiden Diatomeen. Eine Monographie der weltweit bekannten Taxa. Teil 1. Allgemeines und Encyonema. Bibliotheca Diatomologica 36: 1-382.

Krammer, K. (2003). Cymbopleura, Delicata, Navicymbula, Gomphocymbellopsis, Afrocymbella. Diatoms of Europe. Diatoms of the European Inland Waters and Comparable Habitats 4: 1-530.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Navicymbula pusilla CAS

North American Diatom Ecological Database (NADED)

NADED ID: 47309

Autecology Discussion

Navicymbula pusilla is found in waters of high mineral content.

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

Navicymbula pusilla

EMAP Response Plots

Navicymbula pusilla

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.