Hustedt 1943 Category: Symmetrical biraphid
BASIONYM: Navicula minuscula var. alpestris Hustedt in A. Schmidt et al. 1934
Contributor: Loren Bahls - October 2012
Length Range: 16-19 µm
Width Range: 5.8-6.8 µm
Striae in 10 µm: 28-32
Valves are elliptic with rostrate to subcapitate apices. The axial area is very narrow, barely wider than the filiform raphe. The central area is narrow to essentially absent, rectangular in the apical axis. Raphe branches are slightly bowed and widen gradually from the apices towards the proximal ends, which are weakly inflated. Distal raphe ends are both curved toward the secondary side of the valve (confirmed under SEM). Striae are radiate near the valve center and become parallel near the apices. A shortened stria sometimes appears next to the central area. Areolae are round, about 35-40 in 10 µm and difficult to resolve in LM.
Basionym: Navicula minuscula var. alpestris
Author: Hustedt in A. Schmidt et al. 1934
Length Range: µm
Striae in 10 µm:
Originally published without description
Hustedt, F. (1943). Die Diatomeenflora einiger Hochgebirgsseen der Landschaft Davos in den schweizer Alpen. Internationale Revue der gesamten Hydrobiologie und Hydrographie 43:124-197, 225-280.
Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Süsswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.
Schmidt, A. (-). (1874-1959). Atlas der Diatomaceen-Kunde, von Adolf Schmidt, continued by Martin Schmidt, Friedrich Fricke, Heinrich Heiden, Otto Muller, Friedrich Hustedt. Reprint 1984, Koeltz Scientific Books, Konigstein, 480 plates.
Simonsen, R. (1987). Atlas and Catalogue of the Diatom Types of Friedrich Hustedt. J. Cramer, Berlin & Stuttgart 1: 525 pp.
Navicula detenta is widely distributed in small headwater lakes and streams in the mountains of the Pacific Northwest. Here it prefers cool, slightly alkaline waters with low concentrations of nutrients and dissolved solids (see table below). Krammer & Lange-Bertalot (1986) report N. detenta as a northern-alpine species in Europe. It was originally described from high mountain lakes in the Swiss Alps (Hustedt 1943).
Paradise Spring Brook, Glacier National Park, Montana: home of Navicula detenta.
Credit/Source: Loren Bahls
Abundance-weighted means of selected water quality variables measured concurrently with the collection of samples containing Navicula detenta.
Credit/Source: Montana Diatom Database
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.