• Category
  • Length Range
    29.8-48.1 µm
  • Width Range
    6.9-9.4 µm
  • Striae in 10 µm
    12 (dorsal) to 16 (ventral) at the valve center, 17-20 near the apices



Valves are only slightly dorsiventral and lanceolate to rhombic-lanceolate with weakly protracted, narrowly rounded apices. The axial area is moderately wide and merges with a somewhat wider central area to form a narrow longitudinal lanceolate shape, positioned just ventral of the apical axis. The raphe is lateral. Proximal raphe ends are somewhat inflated and deflected toward the ventral side. Terminal raphe fissures are hooked toward the dorsal side. Striae are coarsely punctate and radiate throughout. Areolae number 24-26 in 10 µm.


Cymbopleura rupicola has been collected from a seep along the Going-To-The-Sun Road in Glacier National Park, Montana, and from the Belly River in Waterton Lakes National Park, Alberta (photo below). On the date the Belly River sample was collected, pH measured 8.00, specific conductance measured 183 µS/cm, and water temperature measured 13.3 degrees C. Krammer (2003) reports this species as widely distributed in the temperate zone, especially in the mountains, and preferring oligotrophic waters with moderate electrolyte content.

P1000944 1
Credit: Barb Johnston, Parks Canada
Belly River below Chief Mountain Highway, Waterton Lakes National Park, Alberta: home of Cymbopleura rupicola.

Original Description

Original illustrations published without description.

  • Basionym
    Cymbella rupicola
  • Author
    Grunow in Schmidt et al. 1881

Original Images

Cymbopleura rupicola orig illus

Cite This Page

Bahls, L. (2012). Cymbopleura rupicola. In Diatoms of North America. Retrieved May 29, 2024, from https://diatoms.org/species/cymbopleura_rupicola


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