• Category
  • Length Range
    93-154 µm
  • Width Range
    11-14 µm
  • Striae in 10 µm



Valves are linear, with parallel sides and broadly rounded apices. The valves are narrow, so that the length to width ratio is relatively high. The axial area is broad at nearly 1/2 of the cell width. The raphe is lateral. The proximal raphe ends are drop-shaped and bent slightly toward the primary side of the cell. Striae are very slightly radiate in the center becoming slightly convergent near the apices. A longitudinal line crossing the striae is visible in LM.

The taxon P. paulensis Grunow in Cleve 1895 may be conspecific with P. kwacksii and work to examine the type material is needed.


This taxon has been documented in lakes in New York (Deep Lake, Merriam Lake).

P paulensis org descrp
Original description of Pinnularia paulensis
P paulensis org img
Original illustration of Pinnularia paulensis

Original Description

  • Author
    Camburn and Charles 2000
  • Length Range
    94-144 µm
  • Width
    12-14 µm
  • Striae in 10µm

Original Images

Pinn kwacksii org img
Pinn kwacksii org descp

Cite This Page

Aycock, L. (2022). Pinnularia kwacksii. In Diatoms of North America. Retrieved June 13, 2024, from https://diatoms.org/species/pinnularia-kwacksii


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