Eunotia faba

Ehrenb. 1837      Category: Eunotioid

REPORTED AS: Eunotia vanheurckii (Patrick & Reimer 1966, p. 210, plate 13, fig. 7) | Eunotia vanheurckii (Camburn & Charles 2000, plate 15, figs. 16-18) | Eunotia faba (Lange-Bertalot et al. 2011, p. 97, figs. 44: 1-23; 45: 1-6) 

Eunotia exigua


Eunotia formica

LM scalebar = 10 µm = 80 pixels.


Contributor: Loren Bahls - January 2014
Length Range: 36-54 µm
Width Range: 8.1-11.1 µm
Striae in 10 µm: 12-15 at valve center, 16-19 near the apices


Valves are asymmetric to the apical axis and variably asymmetric to the transverse axis. Dorsal margins are moderately arched. Ventral margins are weakly concave. The apices are broadly rounded, with a deep notch on the ventral side. Helictoglossae are removed some distance from the apices. Terminal raphe fissures are very short at the junction of the valve face and mantle. Striae are radiate and very finely punctate. Forked, or short, costae occur along the dorsal margin in some specimens. Areolae are difficult to resolve in LM and number 30-35 in 10 µm.

Cite This Page:
Bahls, L. (2014). Eunotia faba. In Diatoms of the United States. Retrieved April 19, 2018, from

Species: Eunotia faba

Contributor: Loren Bahls

Reviewer: Paula Furey


Camburn, K.E. and Charles, D.F. (2000). Diatoms of Low-Alkalinity Lakes in the Northeastern United States. Academy of Natural Sciences of Philadelphia, Special Publication 18, 152 pp.

Ehrenberg, C.G. (1837). Über ein aus fossilen Infusorien bestehendes, 1832 zu Brod verbacknes Bergmehl von der Grenzen Lapplands in Schweden. Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königlich-Preussischen Akademie der Wissenschaften zu Berlin 1837:43-45.

Lange-Bertalot, H., Bak, M., Witkowski, A. and Tagliaventi, N. (2011). Eunotia and some related genera. Diatoms of the European Inland Waters and Comparable Habitats. 6: 747 pp.

Patrick, R.M. (1958). Some nomenclatural problems and a new species and a new variety in the genus Eunotia (Bacillariophyceae). Notulae Naturae 312: 1-15.

Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Eunotia faba CAS

North American Diatom Ecological Database (NADED)

NADED ID: 33172

Autecology Discussion

Eunotia faba has been recorded from two lakes in the North Cascade Mountains of Washington. Patrick in Patrick and Reimer (1966) reports this taxon (as E. vanheurckii) from soft, somewhat dystrophic ponds, lakes and swamps in Maine and Pennsylvania. Camburn and Charles (2000) report this taxon (also as E. vanheurckii) from low-alkalinity lakes in the Adirondack Mountains of New York.


Nada Lake, Chelan County, Washington: home of Eunotia faba.

Credit/Source: Ryan Davis, Adventurers and Scientists for Conservation.

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

Eunotia faba

EMAP Response Plots

Eunotia faba

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.