Patrick 1944 Category: Symmetrical biraphid
BASIONYM: Navicula canalis Patrick 1944
REPORTED AS: Navicula vandamii (Krammer and Lange-Bertalot 1991)
Valves are elliptical-lanceolate to linear-lanceolate with protracted rostrate apices. Valve measurements: length 19.6-25 µm, width 4.1-5.5 µm with 16-19 striae in 10 µm and ca. 20-25 lineolae in 10 µm. Axial area is narrow, and linear. Central area is barely differentiated from the axial area. The raphe is filiform with enlarged proximal raphe ends that deflect towards one side of the valve and distal fissures form a distinct hook down onto the mantle on the opposite side. Striae are lineolate. The striae are radiate at the center to parallel or convergent at the apices. The space between the striae is wider or at least equal to the width of the striae. The central nodule is present on the same side as the deflected proximal fissures.
Basionym: Navicula canalis
Author: Patrick 1944
Length Range: 22 µm
Width Range: 5 µm
Striae in 10 µm: 15-17
Valva linearis paulo lanceolata, ad apices attenuatae rostratae, 22 µ longa, 5µ lata, striis lineatis 15-17 per 10 µ, ad centrum valvae paulo radiatis, ad apices valvae parallelis vel plus minusve convergentibus; area axiali angusta; ad nodulum centralem paulo latiori. Pl.1, fig. 7. Distribution-Brazil: Rio Grande do Sul, current water at roadside, near the Lagua dos Quadros, 385 H. Kleerekoper July: 1941 (A-25741). Type (A-25741), scrapings from a stone only wetted at time of collecting, in a rapid near Lagua dos Quadros 367 H. Kleerekoper June 1941 (A-25734).
Patrick, R.M. (1944). Estudo Limnologico e Biologico das Lagoas da regiao Litoranea Sul- Riograndense II. Some New Diatoms from the Lagoa dos Quadros. Boletin de Museo Naciona, Nova serie, Botanica. 2:6 pp., 9 fig.
Sampling for 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). Streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming). Over 1200 sites on 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.