Lange-Bertalot and Krammer 1999 Category: Symmetrical biraphid
BASIONYM: Stauroneis heinii Lange-Bertalot and Krammer 1999
REPORTED AS: Stauroneis phoenicenteron (Hein 1990)
Contributor: Loren Bahls - December 2011
Length Range: 116-191 µm
Width Range: 22-36 µm
Striae in 10 µm: 15-17
Valves are lanceolate with short, subrostrate, and broadly rounded apices. The axial area is about three times wider than the raphe. The central area is a stauros, somewhat wider toward valve margins and occasionally containing short marginal striae. External raphe fissures are lateral. Proximal raphe endings are somewhat inflated and curved to the secondary side. Terminal raphe fissures are hooked, the hooks opening towards the secondary side. Striae are radiate throughout, more so near the apices. Areolae are distinct and number 15-18 in 10 µm.
Basionym: Stauroneis heinii
Author: Lange-Bertalot and Krammer 1999
Length Range: 125-200 µm
Width Range: 22-29 µm
Striae in 10 µm: 15-18
Valvae stricte lanceolatae apicibus minime curte protractis et late rotundatis, 125-200 µm, 22-29 µm latae. Fissurae raphis conspicue laterales sitae inter se extremis centralibus distincte reverse-lateralibus poris centralibus unilateraliter declinatis. Area axialis satis lata ad mediam versus sensim dilatata. Area centralis fasciam formans fere anguste rectangulatam sive ad margines paulo dilatatam. Striae transapicales modice radiantes in media parte magis in partibus distalibus, 15-18 in 10 µm. Puncta striarum 16-18 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.
Hein, M. (1990). Flora of Adak Island, Alaska: Bacillariophyceae (Diatoms). Bibliotheca Diatomologica (H. Lange-Bertalot, ed.), Band 21, J. Cramer, Berlin, 133 pp.+ 53 plates.
Lange-Bertalot, H. and Genkal, S.I. (1999). Diatoms from Siberia I. Islands in the Arctic Ocean (Yugorsky-Shar Strait). Iconographia Diatomologica 6: 1-292.
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 heinii is widely distributed in ponds, small lakes, and wetlands at lower elevations in the Northern Rockies. Available water quality data suggest that this taxon has a relatively broad ecological amplitude, with pH ranging from 5.5 to 8.5 (mean = 6.5) and specific conductance ranging from 8 to 257 µS/cm (mean = 74 µS/cm). Hein (1990) reported this taxon (as S. phoenicenteron) from Adak Island, Alaska.
Lower Howe Lake, Glacier National Park, Montana: home of Stauroneis heinii.
Credit/Source: Steven Rapelje