(Ehrenberg) Lange-Bertalot, Metzeltin and Witkowski 1996 Category: Symmetrical biraphid
BASIONYM: Navicula capitata Ehrenberg 1838
Contributor: Marina Potapova - February 2011
Length Range: 12-28 µm
Width Range: 4.9-8.5 µm
Striae in 10 µm: 8-11
Valves are elliptical-lanceolate with capitate to subcapitate apices. The axial area is narrow and linear. The central area is small, round or elliptical. The raphe is straight, filiform, with slightly expanded external proximal ends. The distal raphe ends are deflected to the secondary valve side. The striae are biseriate, radiate in the valve center and convergent at the apices. The areolae are elongated and generally oriented in the apical axis. Internally the striae open into shallow alveoli. A hyaline area and one or two apical rows of areolae are present at each end of the valve.
Basionym: Navicula capitata
Author: Ehrenberg 1838
Length Range: µm
Striae in 10 µm:
N. striata, testula brevi ovato-lanceolata, utroque fine constricta obtuse, in centesima lineae parte 10 strias offerens.
Cox, E.J. (1987). Studies on the diatom genus Navicula Bory. VI. The identity, structure and ecology of some freshwater species. Diatom Research 2: 159-174.
Ehrenberg, C.G. (1838). Die Infusionsthierchen als vollkommene Organismen. Ein Blick in das tiefere organische Leben de Natur. erlag von Leopold Voss, Leipzig. pp. 1-xvii, 1-548, pls. 1-64.
Lange-Bertalot, H. (2001). Navicula sensu stricto, 10 genera separated from Navicula sensu lato, Frustulia. Diatoms of Europe 2: 1-526.
Lange-Bertalot, H., Metzeltin, D. and Witkowski, A. (1996). Hippodonta gen. nov. Umschreibung und Begrundung einer neuen Gattung der Naviculaceae. Iconographia Diatomologica 4: 247-275.
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.