Hohn and Hellerman 1963 Category: Symmetrical biraphid
BASIONYM: Navicula caterva Hohn and Hellerman 1963
Valves are lanceolate with subrostrate ends. Striae are radiate at the valve center, becoming parallel to slightly divergent at the ends. Central striae may be bent with shortened striae enclosed by longer neighboring striae. The central area is small and transapically oval to rectangular in shape, occupying about 1/3 of the valve breadth.
Basionym: Navicula caterva
Author: Hohn and Hellerman 1963
Length Range: 10.4-16.6 µm
Width Range: 4.2-5.2 µm
Striae in 10 µm: 16-18
Valva lanceolata, apicibus subrostratis leniter. Longitudo 10.4-16.6 µ. Latitudo 4.2-5.2 µ. Striis latis, punctatis obscure, radiates ad mediampartem, paralelis ad apices 16-18/10 µ. Area axiali lineari. Raphe tenui, directa. Area media parva, rectangulari transapicaliter.
Valve lanceolate, ends slightly subrostrate; length 10.4-16.6 µ, width 4.2-5.2 µ striae broad, indistinctly punctuate, radiate at center, parallel at ends 16-18/10 µ; axial area linear; raphe thin, straight; central area small, transapically rectangular.
Occasionally the center pair of striae are more shortened than illustrated and are enclosed by the adjacent striae.
This species is similar in size and shape to Navicula perparva Hust. (Arch. Hydrobiol. Suppl., 15: 246, pl. 20, figs 16-18, 1937) but differs in that the striae, particularly those at the ends, are coarse and parallel. In N. perparva the striae become quite fine at the ends and are radiate.
Specimen illustrated: GC. 44466, Type. Type locality: Potomac River, Md. Distribution: Type locality and Ridley Creek, Pa.
Cite This Page:
Edlund, M., Potapova, M., and Spaulding, S. (2010). Navicula caterva. In Diatoms of the United States. Retrieved April 28, 2016, from http://westerndiatoms.colorado.edu/taxa/species/navicula_caterva
Species: Navicula caterva
Reviewer: Rex Lowe
Hohn, M.H. and Hellerman, J. (1963). The taxonomy and structure of diatom populations from three Eastern North American rivers using three sampling methods. Transactions of the American Microscopical Society 82(3):250-329.
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.