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Synedra mazamaensis

Sovereign 1958      Category: Araphid
SYNONYM(S): Fragilaria mazamaensis (Sovereign) Lange-Bert. 

Synedra goulardi


Tabellaria fenestrata

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - May 2009
Length Range: 12-38 µm
Width Range: 3–5 µm
Striae in 10 µm: 19-23


Valves are lanceolate with attenuate and capitate ends, slightly swollen in the middle portion, width 3-5 µm, length 12-38 µm. Striae number 19-23 in 10 µm. The external openings of the areolae are apically elongated. Axial area is linear and very narrow. The central area is asymmetrical about the apical median plane, and ghost striae may be present in some specimens. One rimportula is present at a valve apex. Apical pore fields are present at both apices. The pores within the apical porefields are arranged in parallel rows.

Original Description

Author: Sovereign 1958
Length Range: 13-40 µm
Width Range: 3-5 µm
Striae in 10 µm: 19-23

Original Description

Valvae lanceolatae apicibus attenuatis, capitatis, 13-40 µ longae, 3-5 µ latae. Costa media longitudinalis (pseudoraphe) angustissima, area axialis nulla, area centralis unilateralis. Striae transapicales 19-23 in 10 µ, lenissime radiantes.

Original Images

Original text and images reproduced with permission by Blackwell Publishing.

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

Species: Synedra mazamaensis

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Sovereign, H.E. (1958). The diatoms of Crater Lake, Oregon. Transactions of the American Microscopical Society 77(2):96-134.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Synedra mazamaensis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 66062

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

Synedra mazamaensis

EMAP Response Plots

Synedra mazamaensis

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.