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Surirella angusta

Kütz. 1844      Category: Surirelloid
SYNONYM(S): Surirella ovalis var. angusta (Kütz.) Van Heurck  | Surirella ovata var. angusta (Kütz.) A.Cleve | Surirella ovalis var. angusta (Kütz.) Gutw. 

Surirella amphioxys


Surirella arctica

LM scalebar = 10 µm = 40 pixels.


Contributor: Marina Potapova | Jonathan English - November 2010
Length Range: 16-60 µm
Width Range: 6.5-12 µm
Striae in 10 µm: 23-28


Frustules have length to width ratios between 2 and 5. The valve face is flat, isopolar, with cuneate or occasionally capitate apices. In valves beyond 25 µm in length, the sides are straight and parallel, while under 25 µm the frustule can be elliptical. The keel is not raised and no alar wings are visible. Fibulae are present on the interior of the valve surface, 7-8 in 10 µm., Every third or fourth costae on the valve surface is either raised or lowered from the plane of the other costae. These altered costae correspond to the fibulae below the valve surface. Not infrequently, raised costae can arise in double form, where no intermediate lower costae exist. The striae, visible in the SEM, consist of 2-5 rows of areolae situated between the costae, 23-28 in 10 µm. Indentations in the valve face are present around the circumference of the valve are present, having the appearance of large areolae.

Original Description

Author: Kütz. 1844
Length Range: 45 µm
Striae in 10 µm: 5 (probably fibulae)

Original Description

S. minuta lineari-oblonga, a latere primario rectangula, secundario utroque fine aequaliter rotundata, margine subtiliter striata; striis in 1./100”’ 11. Lange bis 1/50”’.

Original Images

Cite This Page:
Potapova, M., and English, J. (2010). Surirella angusta. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Surirella angusta

Contributor: Marina Potapova | Jonathan English

Reviewer: Sam Rushforth


Fabri, R. and Leclercq, L. (1984). Etude écologique des rivières du nord du massif Ardennais (Belgique): flore et végétation de diatomées et physico-chimie des eaux. 1. Contexte mésologique, méthodes, analyses physico-chimiques, synthèse taxonomique, écologique et floristeique, iconographie, bibliographie. . Univ. Liège, Station Sci. Hautes-Fagnes, Robertville, Belgique: 379 pp.

Helmcke J.G. and Krieger, W. (1953). Diatomeenschalen im elektronenmikroskopischen Bild. Volume I: pls. 1-102. Transmare Photo, Berlin-Wilmersdorf.

Krammer, K. and Lange-Bertalot, H. (1988). Bacillariophyceae. 2. Teil: Bacillariaceae, Epithemiaceae, Surirellaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Susswasserflora von Mitteleuropa, Band 2/2. Gustav Fisher Verlag, Jena.

Kützing, F.T. (1844). Die kieselschaligen Bacillarien oder Diatomeen. Nordhausen. 152 pp., 30 pls.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA

California Academy of Sciences (CAS)

Surirella angusta CAS

NCBI Genbank Taxonomy

Surirella angusta NCBI

North American Diatom Ecological Database (NADED)

NADED ID: 65002

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

Surirella angusta

EMAP Response Plots

Surirella angusta

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.