Planothidium abbreviatum

(Reimer) Potapova 2012      Category: Monoraphid
BASIONYM: Achnanthes lanceolata var. abbreviata Reimer 1966

Plagiotropis lepidoptera var. proboscidea


Planothidium apiculatum

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - November 2011
Length Range: 11-18 µm
Width Range: 6.1-8.5 µm
Striae in 10 µm: 11-12


Valves are elliptic-lanceolate with subrostrate apices. The raphe valve has a transversely rectangular to elliptic central area. The rapheless valve has a wide rhomboid axial area and asymmetric central area that contains a hood on the internal valve surface. The raphe is straight with expanded external proximal ends. The multiseriate striae are radiate on both valves.

Original Description

Basionym: Achnanthes lanceolata var. abbreviata
Author: Reimer 1966
Length Range: 11-26 µm
Width Range: 6-8.5 µm
Striae in 10 µm: 10-12

Original Description

Pseudoraphe valve with shortened striae forming a broad, lanceolate pseudoraphe. Other features as in the nominate variety. Length 11-26 µ. Breadth 6-8.5 µ. Striae 10-12 in 10 µ.

Original Images

Cite This Page:
Potapova, M. (2011). Planothidium abbreviatum. In Diatoms of the United States. Retrieved April 24, 2018, from

Species: Planothidium abbreviatum

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Potapova, M. (2012). New species and combinations in monoraphid diatoms (Family Achnanthidiaceae) from North America. Diatom Research 27(1): 29-42. doi:10.1080/0269249X.2011.644636

Reimer, C.W. (1966). Consideration of fifteen diatom taxa (Bacillariophyta) from the Savannah River, including seven described as new. Notulae Naturae (Academy of Natural Sciences of Philadelphia) 397:1-15.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA

California Academy of Sciences (CAS)

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

Planothidium abbreviatum

EMAP Response Plots

Planothidium abbreviatum

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.