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Mastogloia lacustris

(Grunow) Van Heurck 1880      Category: Symmetrical biraphid
BASIONYM: Mastogloia smithii var. lacustris Grunow 1878

Mastogloia grevillei


Mastogloia pseudosmithii

LM scalebar = 10 µm = 80 pixels.


Contributor: Pat Kociolek - March 2011
Length Range: 30-54 µm
Width Range: 8-10 µm
Striae in 10 µm: 15-17


Valves are linear-lanceolate with margins slightly convex to nearly straight and apices bluntly produced. The axial area is straight, narrow and expanded to form an asymmetric, elliptic to nearly rectangular central area. The raphe is straight and filiform, becoming lateral at about ½ the way between the apex and central area. External proximal raphe ends are enlarged. Striae are distinctly punctate and radiate, except at the apices where they are parallel.

Co-occurs with the nominate variety in alkaline, lentic habitats.

Original Description

Basionym: Mastogloia smithii var. lacustris
Author: Grunow 1878
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Kociolek, P. (2011). Mastogloia lacustris. In Diatoms of the United States. Retrieved May 20, 2018, from

Species: Mastogloia lacustris

Contributor: Pat Kociolek

Reviewer: Sarah Spaulding


Lee S.S., Gaiser E.E., Van de Vijver, B., Edlund, M.B., and Spaulding, S.A. (2014). Morphology and typification of Mastogloia smithii and M. lacustris, with descriptions of two new species from the Florida Everglades and the Caribbean region. Diatom Research. doi:10.1080/0269249X.2014.889038

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Mastogloia lacustris CAS

North American Diatom Ecological Database (NADED)

NADED ID: 43004

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

Mastogloia lacustris

EMAP Response Plots

Mastogloia lacustris

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.


- Change in rank

This taxon was reported here as M. smithii var. lacustris Grunow until this date. The publication, Lee et al. 2014, documents that M. smithii var. lacustris Grunow is recognized at the rank of species as M. lacustris (Grunow) Van Heurck and it is now updated, with approval of P. Kociolek. - S. Spaulding