• Category
  • Length Range
    22-45 µm
  • Width Range
    5.2-6.7 µm
  • Striae in 10 µm



Valves are linear with apices that are capitate in larger specimens to slightly protracted in smaller specimens. The axial area is lanceolate widening into a large central area reaching the valve margins. The raphe is almost straight, with proximal ends deflected to one side. Striae are often slightly bent, radiate near the valve center and become extremely convergent at the apices.

Note that some specimens from US have a higher stria density than specified in the original description. Most specimens in the study populations, however, had stria density that fit the original description of P. saprophila.


Original Description

  • Author
    Lange-Bert., H.Kobayasi and Krammer in Krammer 2000
  • Length Range
    21-45 µm
  • Width
    5.7-7.5 µm
  • Striae in 10µm

Original Images

P Saprophila Description030

Cite This Page

Potapova, M., O'Malley, I. (2013). Pinnularia saprophila. In Diatoms of North America. Retrieved July 24, 2024, from https://diatoms.org/species/pinnularia_saprophila


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