Encyonopsis krammeri

E.Reichardt 1997      Category: Asymmetrical biraphid

REPORTED AS: Encyonopsis krammeri (Krammer 1997, p. 99, figs 144: 12-15, 21; 145: 1-14, 16-18) 

Encyonopsis hustedtii


Encyonopsis lacuscaerulei

LM scalebar = 10 µm = 80 pixels.


Contributor: Loren Bahls - May 2013
Length Range: 11-21 µm
Width Range: 2.9-4.4 µm
Striae in 10 µm: 25-30


Valves are narrowly lanceolate and moderately dorsiventral with rostrate apices that are deflected slightly ventrally. The dorsal margin is arched and the ventral margin is straight or weakly convex. The axial area is narrow, located 1/3 to 1/2 the distance from the ventral margin to the dorsal margin. The central area is very small and continuous with the axial area. Raphe branches are filiform and bowed, concave to the dorsal margin. Proximal raphe ends are unexpanded and deflected dorsally. Distal raphe fissures are hooked toward the ventral margin. Striae are weakly radiate.

Original Description

Author: E.Reichardt 1997
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Bahls, L. (2013). Encyonopsis krammeri. In Diatoms of the United States. Retrieved April 20, 2018, from http://westerndiatoms.colorado.edu/taxa/species/encyonopsis_krammeri

Species: Encyonopsis krammeri

Contributor: Loren Bahls

Reviewer: Mark Edlund


Bahls, L. (2013). Encyonopsis from western North America: 31 species from Alberta, Idaho, Montana, Oregon, South Dakota, and Washington, including 17 species described as new. Northwest Diatoms, Volume 5. The Montana Diatom Collection, Helena, 46 pp.

Krammer, K. (1997). Die cymbelloiden Diatomeen. Eine Monographie der weltweit bekannten Taxa. Teil 2. Encyonema part., Encyonopsis and Cymbellopsis. Bibliotheca Diatomologica 37:1-469.

Reichardt, E. (1997). Bermerkenswerte Diatomeenfunde aus Bayern. IV. Zwei neue Arten aus den Kleinen Ammerquellen. Berichte der Bayerischen Botanischen Gesellschaft (zur Erforschung der heimischen Flora) 68: 61-66.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Encyonopsis krammeri CAS

North American Diatom Ecological Database (NADED)

NADED ID: 203010

Autecology Discussion

Encyonopsis krammeri has been collected from several lakes in the northern Rocky Mountains of northwest Montana. The pH of these lakes ranged from 8.0 to 9.1 and specific conductance ranged from 93 to 164 μS/cm.


Bullhead Lake, Glacier National Park, Montana: home of Encyonopsis krammeri.

Credit/Source: Loren Bahls

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

Encyonopsis krammeri

EMAP Response Plots

Encyonopsis krammeri

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.