Lange-Bertalot, Kulikovskiy and Witkowski 2010 Category: Symmetrical biraphid
BASIONYM: Boreozonacola hustedtii Lange-Bertalot, Kulikovskiy and Witkowski 2010
REPORTED AS: Naviculadicta pseudosilicula (Lange-Bertalot and Metzeltin 1996) | Naviculadicta pseudosilicula (Lange-Bertalot and Genkal 1999) | Navicula pseudosilicula (Hustedt 1942)
Contributor: Loren Bahls - December 2011
Length Range: 21-46 µm
Width Range: 5.4-9.4 µm
Striae in 10 µm: 18-21
Valves are linear, inflated in the center and sub-terminally to appear triundulate. Apices are cuneate and obtusely rounded. The axial area is very narrow. The central area is about half the width of the valve and circular. The raphe is weakly lateral with simple proximal ends curved toward the primary side of the valve. Distal raphe ends are hooked toward the secondary side. Striae are radiate in the middle and become parallel at the apices. Areolae are easily distinguished in LM and number 20-24 in 10 µm.
Further work is needed to determine the relation of B. hustedtii with Navicula lacuna Patrick & Freese 1961. Kulikovskiy et al. (2010) suggest that N. lacuna may be conspecific with N. pseudosilicula.
Basionym: Boreozonacola hustedtii
Author: Lange-Bertalot, Kulikovskiy and Witkowski 2010
Length Range: 14-50 µm
Width Range: 4.5-10.0 µm
Striae in 10 µm: 17-18
Valves linear, consistently inflated in the middle, minor inflated parts below the apices at least common in larger cell cycle stages; ends slightly cuneate obtusely rounded. Length 14-50 µm, breadth 4.5-10.0 µm i.e. comparatively a very wide size spectrum. Raphe characters as described for the genus. Axial area narrow, linear. Central area rather variable in size, in longer specimens larger, almost circular. Striae 17-18 in 10 µm. Areolae 20-22 in 10 µm.
Hustedt, F. (1942). Diatomeen aus der Umgebung von Abisko in Schwedisch-Lappland. Archiv für Hydrobiologie 39(1): 87-174 .
Kulikovskiy, M.S., Lange-Bertalot, H., Witkowski, A., Dorofeyuk, N.I. and Genkal, S.I. (2010). Diatom assemblages from Sphagnum bogs of the world. I. Nur bog in northern Mongolia. Bibliotheca Diatomologica 55: 1-326.
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.
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.
Patrick, R.M. and Freese, L.R. (1961). Diatoms (Bacillariophyceae) from Northern Alaska. Proceedings of the Academy of Natural Sciences of Philadelphia 112(6):129-293.
Zimmermann, C., Poulin, M. and Pienitz, R. (2010). Diatoms of North America: The Pliocene-Pleistocene freshwater flora of Bylot Island, Nunavut, Canadian High Arctic. Iconographia Diatomologica (H. Lange-Bertalot, ed.), Volume 21, A.R.G. Gantner Verlag K.G., Ruggell, 407 pp.
Boreozonacola hustedtii has been found in Lower Lost Lake, Deer Lodge County, Montana, at an elevation of 2896 meters above mean sea level. The pH of Lower Lost Lake is 6.9 and the specific conductance is 14 µS/cm. Zimmermann et al. (2010) summarize the ecology and distribution of this taxon as follows: “This common freshwater taxon is oligohalobe (indifferent), pH circumneutral and particularly frequent in arctic, alpine and boreal regions of northern Europe, Asia and North America, such as Alaska including Adak Island, as well as the Siberian Islands. In central Europe, [B. hustedtii] occurs dispersed in oligotrophic water bodies of the Alps with low electrolyte content.” B. hustedtii has also been reported from Nur Bog in northern Mongolia (Kulikovskiy et al. 2010).
Lower Lost Lake, elev. 2896 m, Anaconda-Pintlar Wilderness, Deer Lodge County, Montana: home of Boreozonacola hustedtii.