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Neidiopsis wulffii

(J.B.Petersen) Lange-Bert. in Lange-Bert. and Genkal 1999      Category: Symmetrical biraphid
BASIONYM: Navicula wulffii J.B.Petersen 1924

Neidiopsis weilandii


Neidium bobmarshallensis

LM scalebar = 10 µm = 80 pixels.


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.

Original Description

Basionym: Navicula wulffii
Author: J.B.Petersen 1924
Length Range: 35 µm
Width Range: 8.8 µm
Striae in 10 µm: 18

Original Description

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.

Original Images

Cite This Page:
Bahls, L. (2012). Neidiopsis wulffii. In Diatoms of the United States. Retrieved May 21, 2018, from

Species: Neidiopsis wulffii

Contributor: Loren Bahls

Reviewer: Sarah Spaulding


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.

Bahls, L.L. (2014). Neidiopsis hamiltonii sp. nov., N. weilandii sp. nov., N. levanderi and N. wulffii from western North America. Diatom Research. 10.1080/0269249X.2014.889606

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.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Neidiopsis wulffii CAS

North American Diatom Ecological Database (NADED)

NADED ID: 8998005

Autecology Discussion

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