• Category
  • Length Range
    183-232 µm
  • Width Range
    29-34 µm
  • Striae in 10 µm



Valves are linear, with a slightly gibbous center and broadly rounded apices. Axial area is linear. Central area is elliptic and slightly wider on the primary valve side. Striae are radiate at the valve center. Striae are convergent and slightly bent at the apices. A boundary of the internal alveolae openings is visible in LM as a longitudinal line that is positioned close to the axial area. The raphe is lateral, with proximal raphe ends that are drop-shaped and deflected to primary side. The terminal raphe fissures are hook-shaped.


Pinnularia pulchella var. canadensis is found in lakes of Northeastern United States.

Original Description

  • Author
    Krammer 2000
  • Length Range
    180-225 µm
  • Width
    32-35 µm
  • Striae in 10µm

Original Images

Pinnularia Pulchella Canadensis Orig Ill
Pinnularia pulchella var canadensis orig desc 1

Cite This Page

Kersey, M., Potapova, M. (2022). Pinnularia pulchella var. canadensis. In Diatoms of North America. Retrieved July 13, 2024, from https://diatoms.org/species/pinnularia-pulchella-var-canadensis


The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Pinnularia pulchella var. canadensis 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.