Neidium distincte-punctatum Hustedt





Collection 1792a

Other images

More information

Return to Top Page Return to Genera List Return to Species List

Authority information

Hustedt 1922, p.84 fig. 2 (VanLandingham 1978).

Other images

This image was taken utilizing DIC for the specimen above.

More information

This taxon has broad, bluntly rounded ends which are weakly drawn out. The valve is broadly laceolate. The raphe is filiform. The proximal raphe ends are thin, short hooks. The axial area is narrow and a central area is variously developed. Usually expressed as a diagonal region of poorly developed punctae, the central area sometimes appears to be lacking. The striae are oblique to the raphe and valve margin. The submarginal canal is parallel to the valve margin. There are very distinct punctae (Krammer and Lange-Bertalot 1986). This taxon is occasionally found in collections from all of the Great Lakes. Specimens illustrated are from Lake Superior (E.F. Stoermer collection).

  • Type Locality
    Lower Lunz Lake, Austria

  • Holotype
    BRM NE 1/3 (Hustedt Collection, Lunzer Unter See, Finder 622.4)

  • Illustrations
    Simonsen 1987, Pl. 95, Figs. 25-26.

  • Authentic Material
    BRM E6274: CANA 38481.

  • Ecology
    This taxon is found in lake sediments, usually in deep water, or in shaded microhabitats in shallow water bodies. Krammer and Lange-Bertalot 1986 considered it to most likely be a subfossil, but Hamilton et al. 1996 have found it widely distributed in shallow Arctic ponds, and we have observed it in bottom sediments from several modern lakes in central North America as well as in post-Pleistocene lake sediments.

    Size ranges and morphology

  • Length is 32 to 70 micrometers (Krammer and Lange-Bertalot 1986);(Hamilton et al. 1996).
  • Width is12 to 21 micrometers (Krammer and Lange-Bertalot 1986);(Hamilton et al. 1996).
  • Striae are 8 to 12 in 10 micrometers (Krammer and Lange-Bertalot 1986);(Hamilton et al. 1996).
  • Puncta are around 10 to 15 in 20 micrometers(Krammer and Lange-Bertalot 1986);(Hamilton et al. 1996).