Diatoms of North AmericaDiatoms of North America

Pinnularia lagerstedtii

(Cleve) A.Cleve 1934

Pinnularia lagerstedtii guide
  • Category
    Symmetric Biraphid
  • Length Range
    11-26 µm
  • Width Range
    5.2-6.2 µm
  • Striae in 10 µm
    9-10
  • Synonyms
    Pinnularia parva var. lagerstedtii Cleve

  • Reported As
    Pinnularia humilis (Krammer 2000, pg. 28, Figs 18: 5-9.)

Identification

Pinnularia lagerstedtii LM4 Pinnularia lagerstedtii LM2 Pinnularia lagerstedtii LM7 Pinnularia lagerstedtii LM3 Pinnularia lagerstedtii LM5 Pinnularia lagerstedtii LM1 Pinnularia lagerstedtii LM6
View image metadata
Pinnularia Humilis ANSP PF43 022

Description

Valves are linear-elliptic, with slightly convex margins and broadly rounded ends. The axial area is wide, lanceolate, and has a distinct asymmetric central expansion. The raphe is filiform. Proximal raphe ends are deflected to the primary valve side. Striae are short, thick, and slightly radiate in the center to slightly convergent at the ends.

Another species was described, Pinnularia humilis Krammer and Lange-Bert., which is slightly larger than P. lagerstedtii (Lange-Bertalot and Genkal 1999). These two taxa overlap considerably in size and we consider them to be conspecific.

Autecology

Images on this page are from the Alaskan collections of Patrick and Freese (1961). This taxon has also been reported from the Arctic coast of Siberia (Lange-Bertalot and Genkal 1999).

Original Description

  • Basionym
    Pinnularia parva v. lagerstedtii
  • Author
    Cleve 1895
  • Length Range
    25-33 µm
  • Width
    5-8 µm
  • Striae in 10µm
    8.5-10

Original Images

Pinnularia lagersedtii orig illus
Pinnularia lagersedtii orig desc

Cite This Page

Leppik, S., Potapova, M. (2024). Pinnularia lagerstedtii. In Diatoms of North America. Retrieved May 14, 2025, from https://diatoms.org/species/328027/pinnularia-lagerstedtii

Responses

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