Navicula viridula

(Kützing) Ehrenberg 1836      Category: Symmetrical biraphid
BASIONYM: Frustulia viridula Kützing 1833

Navicula vilaplanii


Navicula viridulacalcis subsp. neomundana

LM scalebar = 10 µm = 40 pixels.


Contributor: Marina Potapova - November 2011
Length Range: 50-70 µm
Width Range: 11.2-13.5 µm
Striae in 10 µm: 8-9


Valves are lanceolate to linear-lanceolate with subrostrate apices. The axial area is narrow and straight. The central area is asymmetric; it is trapezoid on the primary side, and semi-circular on the secondary side. The raphe is straight, with external proximal raphe ends slightly dilated and bent toward the primary side of the valve. The central nodule is asymmetrically expanded on the internal valve surface to the primary side. Striae are radiate in the valve center, becoming convergent at the apices. Areolae are usually visible under LM and number 24-25 in 10 μm.

Original Description

Basionym: Frustulia viridula
Author: Kützing 1833
Length Range: µm
Striae in 10 µm:

Original Description

FRUSTULIA VIRIDULA. Ktz. (Fig. 12.) Frustulis minutissimis viridi-lutescentibus, lanceolatis, altero latere truncates, altero acutiusculis, aut opacis aut apicibus hyalines, in strato mucoso nidulantibus. Ich fand sie in einem Teiche bei Markwerben unweit Weissenfels an Hypnum fluitans, so wie auch unter Oscillatorien, mit der folgenden vermischt. Sie bewegte sich.

Original Images

Cite This Page:
Potapova, M. (2011). Navicula viridula . In Diatoms of the United States. Retrieved October 23, 2016, from

Species: Navicula viridula

Contributor: Marina Potapova

Reviewer: Rex Lowe


Ehrenberg, C.G. (1836). Mittheilungen über fossile Infusionsthiere. Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königlich-Preussischen Akademie der Wissenschaften zu Berlin 1836:50-54.

Kützing, F.T. (1833). Synopsis Diatomacearum oder Versuch einer systematischen Zusammenstellung der Diatomeen. Linnaea 8(5): 529-620, pls. XIII-XIX.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Navicula viridula CAS

North American Diatom Ecological Database (NADED)

NADED ID: 46408

Autecology Discussion

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

Navicula viridula

EMAP Response Plots

Navicula viridula

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.