Stauroneis akamina

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

Stauroneis agrestis

 

Stauroneis americana

LM scalebar = 10 µm = 40 pixels.



Observations

Contributor: Loren Bahls - December 2011
Length Range: 63-140 µm
Width Range: 16-24 µm
Striae in 10 µm: 16-22

Description

Valves rhomboid-lanceolate narrowing to rostrate to subcapitate apices. The raphe fissures are lateral, narrowing centrally. The proximal raphe ends are nearly straight with unexpanded pores. The terminal raphe fissures are curved, opening toward the secondary side. The axial area is narrow and linear, widening slightly near the stauros. The stauros typically becomes narrower toward the valve margin, but may be rectangular in some specimens. Occasionally, short striae are present in the central area. Striae are convergent or parallel at the center, becoming radiate toward the apices. The striae number 16-22 in 10 µm. Areolae are elongate and often irregularly spaced, numbering 16-24 in 10 µm (n = 19 valves).



Original Description

Basionym: Stauroneis akamina
Author: Bahls 2010
Length Range: 63-140 µm
Width Range: 16-24 µm
Striae in 10 µm: 16-22

Original Description

Valves rhomboid-lanceolate narrowing to rostrate to subcapitate apices. Length 63-140 µm, width 16-24 µm. Raphe fissures lateral, narrowing to nearly straight proximal endings, which are tipped with unexpanded pores. Terminal raphe fissures curved, opening toward the secondary side. Axial area narrow linear, widening slightly near the central fascia. Central fascia typically becoming narrower toward the valve margins but sometimes rectangular. Occasionally short striae are present in the central area. Striae convergent or parallel at the center, becoming radiate toward the apices, 16-22 in 10 µm. Striae puncta elongate, often irregularly spaced, 16-24 in 10 µm. For measurements, n = 19 valves.

Original Images


Cite This Page:
Bahls, L. (2011). Stauroneis akamina. In Diatoms of the United States. Retrieved December 22, 2014, from http://westerndiatoms.colorado.edu/taxa/species/stauroneis_akamina

Species: Stauroneis akamina

Contributor: Loren Bahls

Reviewer: Sarah Spaulding

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.

Foged, N. (1981). Diatoms in Alaska. Bibliotheca Phycologica, Band 53, J. Cramer, Vaduz, 317 pp.

Hustedt, F. (1930). Bacillariophyta (Diatomeae). In: Die Subwasser Flora Mitteleuropas. (A. Pascher, ed.),10, Gustav Fischer, Jena. 468 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.

Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Stauroneis akamina CAS

North American Diatom Ecological Database (NADED)

NADED ID:

Autecology Discussion

Stauroneis akamina is known from pools in Waterton Lakes National Park, from ponds and fens in Glacier National Park, and from wetlands in southwestern Montana. The pH of these waters ranges from 6.0 to 7.3 and specific conductance ranges from 25 to 71 µS/cm.

Images

Akamina Pools, Waterton Lakes National Park, Alberta: type locality of Stauroneis akamina

Credit/Source: Barb Johnston, Parks Canada