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Denticula tenuis

Kütz. 1844      Category: Nitzschioid
BASIONYM: Denticula tenuis Kütz. 1844

Denticula subtilis


Diadesmis confervacea

LM scalebar = 10 µm = 80 pixels.


Contributor: Pat Kociolek - March 2011
Length Range: 12-20 µm
Width Range: 4 µm
Striae in 10 µm: 22-28


Valves are lanceolate to elliptical-lanceolate, with protracted apices. The raphe is distinct, positioned off center and contained within a canal. Transapical costae are distinct. The striae are punctate. Included in this concept is D. tenuis var. crassula (Naeg. ex Kützing) W. & G.S. West, which appears to represent valves at the lower size range of D. tenuis.

Specimens we have encountered occupy a narrow size range. Patrick and Reimer (1966) give the size range as 6-60 µm long, 3-7 µm broad. Found in alkaline waters across the United States.

Original Description

Basionym: Denticula tenuis
Author: Kütz. 1844
Length Range: µm
Striae in 10 µm:

Original Description

  1. DENTICULA TENUIS. Taf. 17. Fig. VIII. 420/1 D. anguste linearis, margine subtiliter punctata, latere secundario subtiliter striato, anguste lan¬ceolato ; striis transversalibus in 1/100”’ Parte 10-11. Bacillaria palea Nitzsch. Taf. 3. Fig. 3.? Unter Conferven und andern Diatomeen in fliessenden und stehenden Wassergräben bei Nordhausen ! theils einzeln, theils in grössern Haufen beisammen. - Länge bis 1/90‘‘‘. Anmerk. Diese Form hat so grosse Aehnlichkeit mit den einzelnen Gliedern des Diatoma tenue (Taf. 17. Fig. X.), dass ich sie anfangs von diesen nicht verschieden gehalten habe. Später fand ich dieselbe aber sehr häufig immer wieder in diesem losen Zustande, lebend und in Bewegung, wie die Naviculae, und dies hat mich veranlasst, sie hier als besondere Art aufzuführen.

Original Images

Cite This Page:
Kociolek, P. (2011). Denticula tenuis. In Diatoms of the United States. Retrieved May 22, 2018, from

Species: Denticula tenuis

Contributor: Pat Kociolek

Reviewer: Mark Edlund


Hamsher, S.E., Graeff, C.L., Stepanek, J.G. and Kociolek, J.P. (2014). Frustular morphology and polyphyly in freshwater Denticula (Bacillariophyceae) species, and the description of Tetralunata gen. nov. (Epithemiaceae, Rhopalodiales). Plant Ecology and Evolution 147 (3): 346–365. 10.5091/plecevo.2014.990

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

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Denticula tenuis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 25002

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

Denticula tenuis

EMAP Response Plots

Denticula tenuis

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.