• Category
  • Length Range
    8.8-10.8 µm
  • Width Range
    2.5-2.7 µm
  • Striae in 10 µm
  • Synonyms
    Navicula soehrensis var. hassiaca (Krasske) Lange-Bert.
    Chamaepinnularia soehrensis var. hassiaca (Krasske) Lange-Bert.



Valves are linear, with a distinct central expansion. Apices are subcapitate to capitate. The axial area is narrow and linear, expanding slightly toward the center of the valve. The central area is indistinct. The striae are slightly radiate at the center of the valve, transitioning to parallel to slightly convergent at the apices. The raphe is filiform, with relatively widely spaced proximal raphe ends.


Chamaepinnularia hassiaca is a freshwater and aerophytic species (Wetzel et. al. 2013), reported in Europe from streams with siliceous substrata (Lange-Bertalot et al. 2017). We verified C. hassiaca from streams in the southeast U.S. and lakes in the northeast U.S.

Original Description

132. N. Hassiaca nov. spec. –Tafel II, F. 26.—Schalen linear, an den Enden und in der Mitte angeschwollen. Raphe sehr zart. Streifen leicht strahlend, randständig, eine breite lanzettliche Area freilassend, ziemlich kräftig, 16-18 in 10 μ. Länge 12 μ, Breite 3 μ. Selten. Zwischen *Sphagnum* bei Vockerode.

  • Basionym
    Navicula hassiaca
  • Author
    Krasske 1925
  • Length Range
    12 µm
  • Width
    3 µm
  • Striae in 10µm

Original Images

Navicula Hassiaca Original Figure
Navicula Hassiaca Original Description

Cite This Page

Polaskey, M. (2018). Chamaepinnularia hassiaca. In Diatoms of North America. Retrieved May 29, 2024, from https://diatoms.org/species/chamaepinnularia-hassiaca


The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Chamaepinnularia hassiaca from all the stream reaches where it was present. Note that the relative abundance scale is the same on each plot. Explanation of each environmental variable and units are as follows:

ELEVATION = stream reach elevation (meters)
STRAHLER = distribution plot of the Strahler Stream Order
SLOPE = stream reach gradient (degrees)
W1_HALL = an index that is a measure of streamside (riparian) human activity that ranges from 0 - 10, with a value of 0 indicating of minimal disturbance to a value of 10 indicating severe disturbance.
PHSTVL = pH measured in a sealed syringe sample (pH units)
log_COND = log concentration of specific conductivity (µS/cm)
log_PTL = log concentration of total phosphorus (µg/L)
log_NO3 = log concentration of nitrate (µeq/L)
log_DOC = log concentration of dissolved organic carbon (mg/L)
log_SIO2 = log concentration of silicon (mg/L)
log_NA = log concentration of sodium (µeq/L)
log_HCO3 = log concentration of the bicarbonate ion (µeq/L)
EMBED = percent of the stream substrate that is embedded by sand and fine sediment
log_TURBIDITY = log of turbidity, a measure of cloudiness of water, in nephelometric turbidity units (NTU).
DISTOT = an index of total human disturbance in the watershed that ranges from 1 - 100, with a value of 0 indicating of minimal disturbance to a value of 100 indicating severe disturbance.