Kociolek and Stoermer 1988 Category: Asymmetrical biraphid
BASIONYM: Gomphoneis eriense var. angularis Kociolek and Stoermer 1988
Contributor: Pat Kociolek - February 2011
Length Range: 34-67 µm
Width Range: 8-12 µm
Striae in 10 µm: 10-13 at the central portion, 14-16 at the poles
Valves trullate, with broadest portion of the valve outline located towards the footpole from the central nodule. Apices rounded. Raphe distinctly undulate, with rounded external proximal ends. The axial area is narrow, straight, expanded slightly to form a linear-ellipsoidal central area that bears a single, relatively large stigma. A longitudinal line is positioned next to, or near, the axial area. Striae are distinctly biseriate, radiate near the central area, becoming parallel then radiate at the headpole, and becoming strongly radiate at the footpole. A distinct apical pore field is present at the footpole.
Basionym: Gomphoneis eriense var. angularis
Author: Kociolek and Stoermer 1988
Length Range: µm
Striae in 10 µm:
Kociolek, J.P. and Stoermer, E.F. (1988). Taxonomy, ultrastructure and distribution of Gomphoneis herculeana, G. eriense and closely related species (Naviculales: Gomphonemataceae). Proc. Acad. Nat. Sci. Phil. 140: 24-97. http://www.jstor.org/stable/4064935
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.
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.