Lange-Bertalot and Krammer 1996 Category: Symmetrical biraphid
BASIONYM: Stauroneis anceps var. hyalina Peragallo and Brun in Heribaud 1893
REPORTED AS: Stauroneis gracilior (Siver et al. 2005)
Contributor: Loren Bahls - December 2011
Length Range: 32-49 µm
Width Range: 6.0-9.0 µm
Striae in 10 µm: 32-40
Valves are linear-lanceolate with protracted and narrowly rostrate to subcapitate apices. Raphe is weakly lateral, becoming filiform at the distal and proximal ends. Proximal raphe ends are small and straight, and not inflated. The axial area is narrow, barely wider than the raphe, flaring slightly at the stauros. The central area is a rectangular stauros, often asymmetric and slightly wider at the valve margins. Short striae are sometimes present at the margins of the stauros. Striae are radiate throughout. Areolae are irregularly spaced and difficult to resolve in LM.
Basionym: Stauroneis anceps var. hyalina
Author: Peragallo and Brun in Heribaud 1893
Length Range: µm
Striae 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.
Héribaud, J. (1893). Les Diatomées d'Auvergne. Librairie des Sciences Naturelles, Paris. pp. 1-255.
Lange-Bertalot, H. and Metzeltin, D. (1996). Indicators of oligotrophy - 800 taxa representative of three ecologically distinct lake types, Carbonate buffered - Oligodystrophic - Weakly buffered soft water. Lange-Bertalot, H. (ed.), Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 2. Ecology, Diversity, Taxonomy. Koeltz Scientific Books. Königstein, Germany, 2:390 pp.
Siver, P.A., Hamilton, P.B., Stachura-Suchoples, K. and Kociolek, J.P. (2005). Diatoms of North America. The Freshwater Flora of Cape Cod. Iconographia Diatomologica 14: 1-463.
Stauroneis neohyalina is widely distributed in small lakes and wetlands throughout the Northern Rockies. The pH of these waters ranges from 6.2 to 7.6 and specific conductance ranges from 8 to 109 µS/cm. Lange-Bertalot & Metzeltin (1996) reported this species from an electrolyte-poor, humic-rich lake in Finland. Siver et al. (2005) reported this species (as Stauroneis gracilior) from somewhat acidic ponds on Cape Cod, Massachusetts.
Beeskove Lake (right), Missoula County, Montana: home of Stauroneis neohyalina.
Credit/Source: Google Earth