(Grunow) Mann in Round et al. 1990 Category: Symmetrical biraphid
BASIONYM: Navicula cuspidata var. halophila Grunow in Van Heurck 1885
SYNONYM(S): Navicula halophila (Grunow) Cleve
Contributor: Pat Kociolek - March 2011
Length Range: 22-32 µm
Width Range: 5-7 µm
Striae in 10 µm: 15-18
Valves are linear-lanceolate with protracted, rounded apices. The axial area is narrow, straight, expanded to form a narrow sometimes narrowly elliptic central area. The raphe is filiform and straight. The striae are punctate, parallel in the middle, becoming convergent at the apices. There does not appear to be longitudinal striae formed in this morphology.
Patrick and Reimer (1966) and Krammer and Lange-Bertalot (1986) illustrate rhomboid valves for this species, but we have not yet encountered them. The rhomboid valves are without protracted apices, and the two morphologies probably represent two distinct taxa.
Basionym: Navicula cuspidata var. halophila
Author: Grunow in Van Heurck 1885
Length Range: µm
Striae in 10 µm:
var. halophila Grun. (Atl. Suppl. fig. 30.— in Type Ν° 12.) Etroit, très-petit : environ 5 c.d.m. ; stries délicates, 16 environ en 1 c.d.m., radiantes vers la partie moyenne, convergentes aux extrémités. Saumâtre. — Blankenberghe.
Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Susswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.
Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.
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.