Stauroneis americana
Heiden in Schmidt et al. 1903 Category: Symmetrical biraphid
BASIONYM: Stauroneis americana Heiden in A. Schmidt et al. 1903
REPORTED AS: Stauroneis javanica (Hustedt 1959)
LM scalebar = 10 µm = 20 pixels.
Observations
Contributor: Loren Bahls - November 2011
Length Range: 136-214 µm
Width Range: 32-46 µm
Striae in 10 µm: 11-14
Description
Valves are broadly lanceolate with bluntly rounded apices. A prominent pseudoseptum is present at each apex. The axial area is broad and linear, about three times the width of the raphe. The central area is a rectangular stauros, about the same width as the axial area, widening very slightly near the valve margin. The raphe is lateral, becoming filiform near the central area. The proximal raphe ends are nearly straight and weakly expanded. Striae are slightly radiate throughout. Areolae are coarse and number 9-14 in 10 µm.
Original Description
Basionym: Stauroneis americana
Author: Heiden in A. Schmidt et al. 1903
Length Range: µm
Striae in 10 µm:
Original Description
Original Images
Cite This Page:
Bahls, L. (2011). Stauroneis americana. In Diatoms of the United States. Retrieved May 25, 2013, from http://westerndiatoms.colorado.edu/taxa/species/stauroneis_americana
Species: Stauroneis americana
Contributor: Loren Bahls
Reviewer: Sarah Spaulding
Image Credit: Loren Bahls
- Valves large
- Pseudosepta present
- Proximal raphe ends straight
- Stauros rectangular
- Striae slightly radiate
Stauroneis americana has large, broadly lanceolate valves with bluntly-rounded apices and prominent pseudosepta. The proximal raphe ends are straight and weakly expanded. The striae are slightly radiate.
Compare
Stauroneis americana differs from S. finlandia, S. javanica, S. kishinena, and S.ursamaioris by its straight, weakly expanded proximal raphe ends. Stauroneis americana also lacks the distinctly protracted valve apices of S. finlandia and S. ursamaioris.
Stauroneis finlandia
Stauroneis kishinena
Stauroneis javanica
(Grunow) Cleve
Stauroneis ursamaioris
Lange-Bertalot and Van de Vijver
Citations
Bahls, L. (2010). Stauroneis in the Northern Rockies: 50 species of Stauroneis sensu stricto from western Montana, northern Idaho, northeastern Washington and southwestern Alberta, including 16 species described as new. Northwest Diatoms, Volume 4. The Montana Diatom Collection, Helena, 172 pp.
Lange-Bertalot, H. and Genkal, S.I. (1999). Diatoms from Siberia I. Islands in the Arctic Ocean (Yugorsky-Shar Strait). Iconographia Diatomologica 6: 1-292.
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.
Van de Vijver, B., Beyens, L. and Lange-Bertalot, H. (2004). The genus Stauroneis in Arctic and Antarctic Regions. Bibliotheca Diatomologica 50, 312 pp.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID:
Autecology Discussion
Stauroneis americana is widely distributed in wetlands with alkaline pH and low to moderate conductivity, but it is rarely found in abundance. Van de Vijver et al. (2004) published a photo of a Stauroneis americana specimen from Yellowstone National Park (plate 91, fig. 2) and Lange-Bertalot & Genkal (1999) pictured a specimen from “the Rocky Mountains, North America” (Tafel 35, fig. 2).
Images
Bloody Dick Pond #5, Beaverhead County, Montana: Home of Stauroneis americana.
Credit/Source: Loren Bahls