Nitzschia australocommutata

Taxon ID: 66
Author: Hamsher et al. 2016   



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LM image scalebar = 10 µm = 38 pixels      SEM image scalebar = 10 µm  



Observations: Tyler Kohler
Length: 37.7-58.9 µm
Width: 4.-6.3 µm (center valve),
Striae: 18-26 in 10 µm at the center; 20-26 in 10 µm at the ends


Valves linear-lanceolate, narrowing towards the produced, capitate endings; ventral margin concave; dorsal margin parallel to slightly concave. Raphe eccentric, stretching along the valve margin; proximal raphe endings simple; distal raphe endings hooked towards the dorsal margin. Striae parallel throughout; more widely spaced at the center of the valve. Fibulae (keel puncta) variable in size and spacing.

Morphology: Nitzschioid
Distribution: South Victorialand endemic




This diatom was usually encountered in girdle view and often with 'hantzschioid' symmetry, although this appears to be a species of Nitzschia. Our specimens were similar to Nitzschia commutata sensu Krammer and Lange-Bertalot (1988), but had a much smaller size range. Our specimens were also similar to Nitzschia stagnorum sensu Hustedt (1930) but were narrower with more capitate endings. Thus, we propose that this may be a new species of Nitzschia, although we retain the name N. commutata. This specimen was formally referred to as Hantzschia sp.#5 and Nitszchia commutata.


McMurdo Dry Valleys Waterbodies with Nitzschia australocommutata

  • Adams Stream
  • Aiken Creek
  • Bohner Stream
  • Bowles Creek
  • Canada Stream
  • Commonwealth Stream
  • Delta Stream
  • Green Creek
  • Harnish Creek
  • Harnish Creek Tributary
  • Huey Creek
  • Lake Fryxell
  • Lawson Creek
  • Little Sharpe
  • Lost Seal Stream
  • Lyons Tributary (Mason?)
  • McKay Creek
  • Onyx River
  • Priscu Stream
  • Von Guerard Stream
  • Wales Stream
  • Wharton Creek
  • Wormherder Creek

Original Type Description

Author: Hamsher et al. 2016

Original Description:


New combination




Index Nominum Algarum (INA):

  • If an INA link is available, it will be shown above
  • The INA is a bibliographic reference "card file" for algal taxonomy, containing nearly 200,000 names of algae (in the broad sense).

Publications (by year):

  • Hustedt 1930. p. 405, fig. 773. [citation 51(22)]
  • Krammer and Lange-Bertalot 1988. p. 56-57, taf. 42, figs 1-6. [citation 74(53)]

See full publication info assembled for this website