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Diatoma moniliformis

Kütz. 1833      Category: Araphid
SYNONYM(S): Diatoma tenue var. moniliforme Kütz. 

Diatoma ehrenbergii


Diatoma tenuis

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - May 2009
Length Range: 10-40 µm
Width Range: 2.5-6.0 µm
Striae in 10 µm: 50-60


Cells form zig-zag colonies. Frustules are rectangular in girdle view, valves are elliptical to lanceolate with rounded to subrostrate apices, valves are 10-40 µm in length and 2.5-6.0 µm in width. Transapical ribs number 6-11 in 10 µm. Striae are uniseriate and composed of small poroid areolae, 50-60 in 10 µm. Axial area is linear, very narrow. One rimportula is positioned within in a transapical rib at one, or both, valve apices. Apical pore fields are present at both apices.

Original Description

Author: Kütz. 1831
Length Range: µm
Striae in 10 µm:

Original Description

Frustulis quadraticis, longam seriam formatibus.

Original Images

Cite This Page:
Potapova, M. (2009). Diatoma moniliformis. In Diatoms of the United States. Retrieved May 20, 2018, from

Species: Diatoma moniliformis

Contributor: Marina Potapova

Reviewer: Sam Rushforth


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

Williams, D.M. (1985). Morphology, taxonomy and inter-relationships of the ribbed araphid diatoms from the genera Diatoma and Meridion (Diatomaceae: Bacillariophyta). Bibliotheca Diatomologica 8: 1-228.

Williams, D.M. (2012). Diatoma moniliforme: Commentary, relationships and an appropriate name. Nova Hedwigia, Beiheft 141: 255–262.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA
Original INA

California Academy of Sciences (CAS)

NCBI Genbank Taxonomy

Diatoma moniliforme NCBI

North American Diatom Ecological Database (NADED)

NADED ID: 27008

Autecology Discussion

Fresh and brackishwater. Forms zig-zag colonies attached to substrates by a mucilage pad.

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

Diatoma moniliformis

EMAP Response Plots

Diatoma moniliformis

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.