Psammothidium daonense

(Lange-Bert.) Lange-Bert. 1999      Category: Monoraphid
BASIONYM: Achnanthes daonensis Lange-Bert. 1989
SYNONYM(S): Psammothidium grischunum f. daonensis (Lange-Bert.) Bukht. and Round 

Psammothidium curtissimum


Psammothidium didymum

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - August 2010
Length Range: 9-23 µm
Width Range: 4.8-7.5 µm
Striae in 10 µm: 24-30


Valves are elliptical to linear-elliptical. The raphe valve has a linear axial area, which widens into a transapically elliptical, rectangular, or diamond-shaped central area. The raphe is straight, without terminal fissures. The central and terminal raphe ends are slightly expanded externally. The central raphe ends curve toward opposite sides internally. The rapheless valve has a large rhomboid axial area, which has an irregular border. The central area is usually not differentiated from the axial area. Striae are radiate on both valves, 24-30 in 10 µm, interrupted at the valve margin. One row of areolae is present on the mantle of both valves; occasionally a second row of areolae is inserted on the valve margin. Areolae are 36-48 in 10 µm within the striae. The external openings of the areolae are mostly circular, occasionally elongated.

Original Description

Basionym: Achnanthes daonensis
Author: Lange-Bert. 1989
Length Range: 10-26 µm
Width Range: 5-8 µm
Striae in 10 µm: 27-32

Original Description

Valvae ellipticae ad lineari-ellipticae apicibus late rotundatis non protractis, 10-26 μm longae, 5-8 μm latae. Raphovalva: Raphe filiformis recta, poros terminales influens; pori centrales modice approximate. Area axialis anguste linearis area centralis variabiliter transverse dilatata. Areovalva: Area axialis plus minusque late lanceolata influens in aream centralis rhombicam irregulariter marginatum. Striae transapicales modice radiantes in media parte valvarum usque ad apices, 27-32/10 μm. Quamquam similis a A. marginulata, A. kryophila, A. helvetica satis differt.

Original Images

Cite This Page:
Potapova, M. (2010). Psammothidium daonense. In Diatoms of the United States. Retrieved April 19, 2018, from

Species: Psammothidium daonense

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Bukhtiyarova, L. and Round, F. E. (1996). Revision of the genus Achnanthes sensu lato. Psammothidium, a new genus based on Achnanthidium marginulatum. Diatom Research 11: 1-30. 10.1080/0269249X.1996.9705361

Lange-Bertalot, H. (1999). Neue Kombinationen von taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276-289.

Lange-Bertalot, H. and Krammer, K. (1989). Achnanthes eine Monographie der Gattung mit Definition der Gattung Cocconeis and Nachtragen zu den Naviculaceae. Bibliotheca Diatomologica 18, 393 pp. Cramer, Berlin, Stuttgart.

Manoylov, K.M. (2007). On some Psammothidium species from rivers in the United States. Diatom Research 22(2): 317–327.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Psammothidium daonense CAS

NCBI Genbank Taxonomy

Achnanthes daonense NCBI

North American Diatom Ecological Database (NADED)


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

Psammothidium daonense

EMAP Response Plots

Psammothidium daonense

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.