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Frustulia amphipleuroides

(Grunow) A.Cleve 1934      Category: Symmetrical biraphid
BASIONYM: Navicula rhomboides var. amphipleuroides Grunow 1880

Frustulia amosseana


Frustulia asiatica

LM scalebar = 10 µm = 40 pixels.


Contributor: Pat Kociolek | Carrie Graeff - January 2011
Length Range: 63-97 µm
Width Range: 15.0-16.5 µm
Striae in 10 µm: 23-25 in the center, 25-26 at the ends


Valves are linear-lanceolate-rhomboid. The apices are broadly rounded apices and slightly constricted. Across most of the valve, striae are parallel or sometimes slightly radiate. Striae are very slightly convergent at the apices. Striae are radiate at the apices. In the longitudinal direction, the areolae are partially organized giving the longitudinal striae a wavy appearance. Areolae are generally unorganized at the center of the valve and minimal amount of organization is present near the apices. Externally, the openings of the areolae are lanceolate in shape. Internally, the areolae are oval and occluded by hymenes. The raphe branches curve slightly and are enclosed by longitudinal ribs. A very robust and slightly curved porte-crayon is present where the longitudinal ribs and long, linear helictoglossa fuse. The central nodule is elongate and fuses with the longitudinal ribs, which appear to be interrupted at the central area, rather than constricted. External raphe ends are slightly dilated and accompanied by a small, round depression. The central area may have 0-4 isolated poroids. An isolated poroid may also be present near the distal raphe ends.

Original Description

Basionym: Navicula rhomboides var. amphipleuroides
Author: Grunow 1880
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Kociolek, P., and Graeff, C. (2011). Frustulia amphipleuroides. In Diatoms of the United States. Retrieved May 21, 2018, from

Species: Frustulia amphipleuroides

Contributor: Pat Kociolek | Carrie Graeff

Reviewer: Sarah Spaulding


Cleve-Euler, A. (1934). The diatoms of Finnish Lapland. Societas Scientiarum Fennica. Commentationes Biologicae. 4(14):154 pp.

Rumrich, U., Lange-Bertalot, H. and Rumrich, M. (2000). Diatoms of the Andes. From Venezuela to Patagonia/Tierra del Fuego and two additional contributions. Lange-Bertalot, H. (ed.), Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 9. Phytogeography-Diversity-Taxonomy. Koeltz Scientific Books, Königstein, Germany, 9:673 pp.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA

California Academy of Sciences (CAS)

Frustulia amphipleuroides CAS

North American Diatom Ecological Database (NADED)

NADED ID: 35036

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

Frustulia amphipleuroides

EMAP Response Plots

Frustulia amphipleuroides

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.