Stauroneis absaroka

Bahls 2010      Category: Symmetrical biraphid
BASIONYM: Stauroneis absaroka Bahls 2010

Stauroforma exiguiformis

 

Stauroneis acidoclinata

LM scalebar = 10 µm = 40 pixels.



Observations

Contributor: Loren Bahls - December 2011
Length Range: 43-75 µm
Width Range: 10.1-14.7 µm
Striae in 10 µm: 17-19

Description

Valves are lanceolate with subrostrate to subcapitate apices. The axial area is broad, often with an irregular border formed by the ends of striae, widening gradually towards the central area. The central area is a very broad stauros, widening markedly toward the valve margins. Curved striae border the stauros. Shortened striae have not been observed in the central area. The raphe branches are moderately lateral. Proximal raphe ends are strongly curved and tipped with distinctly inflated, drop-like central pores. Striae are radiate throughout and curved about the central area. Striae puncta are distinct and number 22-26 in 10 µm.



Original Description

Basionym: Stauroneis absaroka
Author: Bahls 2010
Length Range: 43-75 µm
Width Range: 10.1-14.7 µm
Striae in 10 µm: 17-19

Original Description

Valves lanceolate with subrostrate to subcapitate ends. Length 43-75 µm, width 10.1-14.7 µm. Axial area wide, often with an irregular border, expanding gradually toward the central area. Central area a very broad butterfly-shaped fascia, widening markedly toward the valve margins. Shortened striae not observed in the central area. Raphe fissures moderately lateral, proximal endings strongly curved and tipped with distinctly inflated, drop-like central pores. Striae curved and radiate throughout, 17-19 in 10 µm. Striae puncta distinct, 22-26 in 10 µm. For measurements, n = 14 valves.

Original Images


Cite This Page:
Bahls, L. (2011). Stauroneis absaroka. In Diatoms of the United States. Retrieved August 21, 2014, from http://westerndiatoms.colorado.edu/taxa/species/stauroneis_absaroka

Species: Stauroneis absaroka

Contributor: Loren Bahls

Reviewer: Sam Rushforth

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.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Stauroneis absaroka CAS

North American Diatom Ecological Database (NADED)

NADED ID:

Autecology Discussion

Stauroneis absaroka has been recorded from five lakes and ponds in southwest Montana. The pH of these waters ranges from 6.1 to 7.8 and specific conductance ranges from 21 to 41 µS/cm. This taxon is uncommon and only a minor component of the diatom assemblage at each location where it was found.

Images

Bloody Dick Pond #3, Beaverhead County, Montana: home of Stauroneis absaroka.

Credit/Source: Loren Bahls