(Petersen) Lange-Bertalot in Lange-Bertalot & Genkal 1999 Category: Symmetrical biraphid
BASIONYM: Navicula wulffii Petersen 1924
Contributor: Loren Bahls - January 2012
Length Range: 39-48 µm
Width Range: 9.4-11.4 µm
Striae in 10 µm: 16-18
Valves are linear-elliptic with broadly rostrate to subcapitate apices. A longitudinal line runs along each side of the valve close to the mantle. The axial area is narrow, barely wider than the raphe. The central area is circular and about one-half the width of the valve at center. The raphe is filiform with simple proximal ends that are deflected to the same side. Striae are strongly radiate in the middle, becoming parallel then weakly convergent near the apices. Areolae in the striae are somewhat elongate and distinct in LM, and number 20-24 in 10 µm.
Basionym: Navicula wulffii
Author: Petersen 1924
Length Range: 35 µm
Width Range: 8.8 µm
Striae in 10 µm: 18
Valve linear-lanceolate, rostrate-capitate, with very slightly triundulate margins. On each side a deep sulcus. L. 35 µ, b. 8,8 µ, striae 18 in 10 µ, radiate throughout, finely punctate. Fig. 1.
Antoniades, D., Hamilton, P.B., Douglas, M.S.V. and Smol, J.P. (2008). Diatoms of North America: The freshwater floras of Prince Petrcik, Ellef Ringnes and northern Ellesmere Islands from the Canadian Arctic Archipelago. Iconographia Diatomologica 17.
Lange-Bertalot, H. (2001). Navicula sensu stricto, 10 genera separated from Navicula sensu lato, Frustulia. Diatoms of Europe 2: 1-526.
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.
Petersen, J.B. (1924). Freshwater-algae from the north coast of Greenland collected by the late Dr. Th. Wulff. Meddelelser om Gronland 64: 305-319.
Neidiopsis wulffii is uncommon in oligotrophic and very low-conductivity lakes and ponds of the Northern Rocky Mountains. In these habitats, pH ranges from 6.40 to 7.57 and specific conductance ranges from 7 to 16 µS/cm. Neidiopsis wulffii was recently reported from Arctic Canada in waters ranging from 18 to 134 µS/cm (Antoniades et al. 2008). Previously, this taxon was known only from the type locality in Greenland (Lange-Bertalot 2001).
Kootenai Lake on the Waterton River, Glacier National Park, Montana: home of Neidiopsis wulffii.
Credit/Source: Loren Bahls