Navicula detenta
Hustedt 1943 Category: Symmetrical biraphid
BASIONYM: Navicula minuscula var. alpestris Hustedt in A. Schmidt et al. 1934
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Loren Bahls - October 2012
Length Range: 15.6-18.8 µm
Width Range: 5.8-6.8 µm
Striae in 10 µm: 28-32
Description
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.
Original Description
Basionym: Navicula minuscula var. alpestris
Author: Hustedt in A. Schmidt et al. 1934
Length Range: µm
Striae in 10 µm:
Original Description
Originally published without description
Original Images
Cite This Page:
Bahls, L. (2012). Navicula detenta. In Diatoms of the United States. Retrieved May 24, 2013, from http://westerndiatoms.colorado.edu/taxa/species/navicula_detenta
Species: Navicula detenta
Contributor: Loren Bahls
Reviewer: Sam Rushforth
Image Credit: Loren Bahls
- Valves elliptic
- Apices rostrate to subcapitate
- Central area linear
- Striae usually complete about central area
Navicula detenta has elliptic valves less than 8 µm wide. Apices are rostrate to subcapitate. The central area is linear in the apical axis and striae are usually complete about the central area.
Compare
Cavinula pusio, which sometimes occurs in the same habitats, has larger valves and alternate short-long-short striae around the central area.
Cavinula pusio
Citations
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.) Susswasserflora 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.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 46486
Autecology Discussion
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).
Images
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