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Stauroneis reichardtii

Lange-Bert., Cavacini, Tagliaventi, and Alfinito 2003      Category: Symmetrical biraphid

REPORTED AS: Stauroneis anceps Sippe 2 (Reichardt 1995) | Stauroneis anceps Sippe 3 (Reichardt 1995) 

Stauroneis pseudagrestis


Stauroneis rex

LM scalebar = 10 µm = 40 pixels.


Contributor: Loren Bahls - December 2011
Length Range: 36-54 µm
Width Range: 8.0-10.8 µm
Striae in 10 µm: 20-26


Valves are linear-elliptical to linear-lanceolate with nearly parallel sides and abruptly protracted, distinctly capitate apices. The axial area is narrow and linear, widening slightly near the stauros. The stauros is relatively wide and shaped like a bow tie. Short striae are sometimes present in the stauros. The raphe is lateral, becoming filiform at the center of the valve. The proximal ends are straight and not (or barely) expanded. Striae are radiate in the middle of the valve and strongly radiate near the apices. Areolae are easy to distinguish in LM and number 24-28 in 10 µm.

Original Description

Author: Lange-Bert., Cavacini, Tagliaventi, and Alfinito 2003
Length Range: 22-48 µm
Width Range: 6.2-11.5 µm
Striae in 10 µm: 21-23

Original Description

Valves linear-elliptical or linear-lanceolate to elliptical-lanceolate, ends abruptly protracted, i.e. distinctly set off capitate to subcapitate (not rostrate as in St. anceps and St. jarensis comparatively). Length 22-48 µm, breadth 6.2-11.5 µm. Pseudosepta lacking. Raphe fissures moderately lateral with rather inconspicuous central pores (LM). Axial area approximately linear and narrow. Central area forming a moderately to rather broad fascia reaching the margins and here more or less expanded. Striae radiate throughout, less near the central area but more towards the ends, 21-23 in 10 µm. Puncta of the striae very easy to discern, also in LM without oblique lighting (as in St. anceps and St. jarensis, unlike *St. amplipora), 22-25 in 10 µm.

Original Images

Cite This Page:
Bahls, L. (2011). Stauroneis reichardtii. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Stauroneis reichardtii

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.

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.

Reichardt, E. (1995). Die Diatomeen (Bacillariophyceae) in Ehrenbergs Material von Cayenne, Guyana Gallica (1843). Volume 1, Iconographia Diatomologica (H. Lange-Bertalot, ed.). Koeltz Scientific Books, Konigstein.

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)

Stauroneis reichardtii CAS

North American Diatom Ecological Database (NADED)

NADED ID: 62101

Autecology Discussion

Stauroneis reichardtii has been collected from several lakes, ponds and wetlands in the Northern Rockies. Measured pH at these sites ranges from 6.5 to 7.6 and specific conductance ranges from 21 to 67 µS/cm. Stauroneis reichardtii was described from material collected from Sardinia (Lange-Bertalot et al. 2003) and has also been found in tropical South America. This taxon is widely distributed in the Arctic (Van de Vijver et al. 2004).


Red Eagle Pond, Glacier National Park, Montana: home of Stauroneis reichardtii.

Credit/Source: E. William Schweiger, National Park Service