Navicula slesvicensis
Grunow in Van Heurck 1880 Category: Symmetrical biraphid
SYNONYM(S): Navicula viridula var. slesvicensis (Grunow in Van Heurck) Grunow in Cleve and Moller
LM scalebar = 10 µm = 40 pixels.
Observations
Contributor: Marina Potapova | Loren Bahls - November 2011
Length Range: 36-69 µm
Width Range: 10-12.5 µm
Striae in 10 µm: 8-9
Description
Valves are linear-elliptic to linear-lanceolate with apices that are wedge-shaped in smaller specimens and more produced, subrostrate in larger specimens. The axial area is narrow and straight. The central area is transversely elliptic or irregularly rhomboid. The raphe is straight, moderately lateral, with dilated external proximal raphe ends. The central nodule is symmetric. Striae are radiate in the valve center, more widely spaced about the central area and convergent at the apices. The areolae are visible under LM and number approximately 25 in 10 μm.
Original Description
Basionym:
Author: Grunow in Van Heurck 1880
Length Range: µm
Striae in 10 µm:
Original Description
Original Images
Cite This Page:
Potapova, M., and Bahls, L. (2011). Navicula slesvicensis . In Diatoms of the United States. Retrieved May 21, 2013, from http://westerndiatoms.colorado.edu/taxa/species/navicula_slesvicensis
Species: Navicula slesvicensis
Contributor: Marina Potapova | Loren Bahls
Reviewer: Rex Lowe
Image Credit: Loren Bahls, Marina Potapova
- Valves linear-elliptic to linear-lanceolate
- Central area transversely elliptic or irregularly rhomboid
- External proximal raphe ends dilated
- Central nodule symmetric
- Areolae visible under LM
Valves are linear-elliptic to linear-lanceolate, with apices that are wedge-shaped in short specimens and more produced and subrostrate in longer specimens. The central area is transversely elliptic or irregularly rhomboid. External proximal raphe endis are dilated. The central nodule is symmetric. Striae are radiate in the valve center, more widely spaced around the central area and convergent at the apices. The areolae are visible under LM, approximately 25 in 10 μm.
Compare
Navicula slesvicensis differs from N. viridula and N. viridulacalcis by a symmetric central nodule and straight, dilated external proximal raphe ends. Navicula streckerae has smaller, more slender valves with narrower ends and coarser areolae. Navicula vaneei has more lanceolate valves without protracted ends.
Navicula viridulacalcis subsp. neomundana
Navicula viridula
Navicula streckerae
Navicula vaneei
Citations
Lange-Bertalot, H. (2001). Navicula sensu stricto, 10 genera separated from Navicula sensu lato, Frustulia. Diatoms of Europe 2: 1-526.
Van Heurck, H. (1880). Synopsis des Diatomées de Belgique. Atlas. Ducaju & Cie., Anvers.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 46732
Autecology Discussion
Navicula slesvicensis has been reported from creeks and rivers in Montana, North Dakota and Wyoming, where it prefers warm, muddy waters rich in sodium sulfate and organic nitrogen. Common diatom associates of N. slesvicensis in these streams include Navicula peregrina, Entomoneis paludosa, Navicula salinarum, Ctenophora pulchella, Entomoneis alata, Biremis circumtexta, Craticula halophila, Tabularia fasciculata, Pleurosigma delicatulum, Fragilaria famelica, Navicula goersii, and Fallacia tenera. In Europe, Navicula slesvicensis is found in electrolyte-rich freshwaters and in coastal waters, estuaries, and inland salt springs (Lange-Bertalot 2001).