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Stauroneis schroederi

Hust. in A.Schmidt 1913      Category: Symmetrical biraphid

Stauroneis sacajaweae


Stauroneis separanda

LM scalebar = 10 µm = 80 pixels.


Contributor: Loren Bahls - December 2011
Length Range: 40-64 µm
Width Range: 7.4-11.1 µm
Striae in 10 µm: 24-28


Valves are lanceolate with gradually attenuated, narrowly rostrate to subcapitate apices. The axial area is about three times wider than the raphe and linear, widening slightly near the narrow stauros. Short striae are sometimes present in the stauros. The raphe is weakly lateral. Proximal raphe ends are nearly straight (deflected slightly to the primary side) and not expanded. Striae are parallel at the center, becoming radiate near the apices. Areolae are variably spaced and number 22-28 in 10 µm.

Original Description

Author: Hust. in A.Schmidt 1913
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Bahls, L. (2011). Stauroneis schroederi. In Diatoms of the United States. Retrieved May 24, 2018, from

Species: Stauroneis schroederi

Contributor: Loren Bahls

Reviewer: Marina Potapova


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.

Hustedt, F. (1914). Bacillariales aus den Sudeten und einigen benachbarten Gebieten des Odertales. Arch. Hydrobiol. 10: 1-128.

Lange-Bertalot, H., Cavacini, P., Tagliaventi, N. and Alfinito, S. (2003). Diatoms of Sardinia: Rare and 76 new species in rock pools and other ephemeral waters. Iconographia Diatomologica 12, 438 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)

Original INA

California Academy of Sciences (CAS)

Stauroneis schroederi CAS

North American Diatom Ecological Database (NADED)


Autecology Discussion

Stauroneis schroederi is very rare in the Northern Rockies. To date it has been found only in one lake and a small pond. The pH of the lake (Beeskove) is 7.4 and the specific conductance is 10 µS/cm. The pH of the pond (Bloody Dick #5) is 7.8 and the specific conductance is 41 µS/cm. The type locality of this taxon is Wilhelmtal in the Sudeten Mountains of Silesia, southwest Poland. Lange-Bertalot et al. (2003) reported this species from Sardinia.


Bloody Dick Pond #5, Beaverhead County, Montana: home of Stauroneis schroederi.

Credit/Source: Loren Bahls