• Category
  • Length Range
    23.4-71.7 µm
  • Width Range
    4.9-6.7 µm
  • Striae in 10 µm



Frustules lanceolate in girdle view because of amphoroid symmetry. Valves strongly arcuate with convex dorsal and concave ventral margins; margins parallel in larger valves, more dorsally arched in smaller valves. Ends slightly protracted in longer valves, acutely rounded in shorter valves. Small but distinct helictoglossae located subterminally along ventral margin. Two rimoportulae per valve, located at each valve end. Striae parallel, slightly finer density at valve ends.


Eunotia charliereimeri is currently known only from its type locality, Bear Meadows Bog in Pennsylvania. Bear Meadows is classified as a poor fen and its open wetland is dominated by Sphagnum, sedges, swamp laurel (Kalmia polifolia), blueberry (Vaccinium spp.), and sundews (Drosera rotundifolia). The woody plants Rhododendron (spp.), alder (Alnus spp.), Spiraea (spp.), and mountain holly (Nemopanthus mucronatus) form the border between the open wetland and surrounding forest. L.B. has measured water chemistry in the bog for many years with pH values as low as 4.0 and as high as 5.0, and electrical conductivity measurements from 19 to 38 µS (Orion Model 24). Diatom taxa found with E. charliereimeri in Bear Meadows Bog include E. tauntoniensis, E. flexuosa, E. curvata, E. naegelii, E. paludosa var. trinacria, E. serra, Fragilariforma constricta, Frustulia rhomboides var. saxonica, Pinnularia subcapitata, P. hilseana, P. abaujensis, Stenopterobia delicatissima, Aulacoseira spp., and Neidium spp.

Bear  Meadows Lowres
Credit: Lynn Brant
Bear Meadows Bog, Pennsylvania.

Original Description

Frustules sublanceolate in girdle view with truncate ends. Valve lunate or arcuate, with strongly convex dorsal margin and concave ventral margin, 4.9-6.7 μm wide, 23.5-71.4(84.0?) μm long. Apices of valve acute or rounded, narrowing to slightly attenuated ends. Short terminal raphe nodules are distinct on the ventral margin and slightly removed from the apices. Two rimoportulae per valve, one rimoportula at each valve end. Striae are fine and parallel, 17.0-20.8 in 10 μm, and somewhat finer at the valve ends.

  • Author
    Edlund and L.A.Brant 2010
  • Length Range
    23.5-71.4 µm
  • Width
    4.9-6.7 µm
  • Striae in 10µm

Original Images

Type  Eun Cwr  Edlund Et  Brant 2010

Cite This Page

Edlund, M, and Burge, D, and Brant, L. (2017). Eunotia charliereimeri. In Diatoms of North America. Retrieved August 19, 2018, from https://diatoms.org/species/eunotia_charliereimeri


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