Van de Vijver and Lange-Bertalot 2004 Category: Symmetrical biraphid
BASIONYM: Stauroneis bryocola Van de Vijver and Lange-Bertalot 2004
Contributor: Loren Bahls - December 2011
Length Range: 41-58 µm
Width Range: 8.3-9.8 µm
Striae in 10 µm: 27-30
Valves are lanceolate with gradually attenuated, subtly protracted, and broadly rounded rostrate apices. The axial area is narrow and widens slightly near the central area. The central area is a rectangular stauros. Short striae are sometimes present at the margins. The raphe is lateral with straight proximal ends. Striae are slightly radiate in the middle, becoming more radiate toward the apices. Areolae are irregularly spaced, difficult to resolve in LM and number 24-30 in 10 µm.
Basionym: Stauroneis bryocola
Author: Van de Vijver and Lange-Bertalot 2004
Length Range: 40-57 µm
Width Range: 7-8.5 µm
Striae in 10 µm: 24-27
Valves lanceolate to rhomboidal-lanceolate with protracted, rostrate-subcapitate ends. Pseudosepta absent. Length 40-57 µm, breadth 7-8.5 µm. Axial area narrow to moderately broad, linear, only slightly rhombically expanded near the central area. Central area forming an almost rectangular fascia, not expanded towards the valve margins. Raphe fissures lateral. Central endings straight, never curved to the very small, indistinct central pores. Striae slightly to moderately radiate in the middle, more radiate near the valve ends, 24-27 in 10 µm. Puncta of the striae irregularly spaced, 25-30 in 10 µm.
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.
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.
Stauroneis bryocola is known from four lakes and ponds in southwestern Montana. The pH of these waters ranges from 6.5 to 7.8 and specific conductance ranges from 21 to 41 µS/cm. The type locality for Stauroneis bryocola is Heard Island in the sub-Antarctic Region, where it was found among wet mosses in some small tarns (Van de Vijver et al. 2004).
Bloody Dick Pond No. 2, Beaverhead County, Montana: home of Stauroneis bryocola.
Credit/Source: Loren Bahls