Valves are lanceolate with rounded subrostrate apices. Valves are distinctly dorsiventral in small specimens, slightly dorsiventral in larger specimens. Axial and central areas are very wide, 1/3 to 1/2 the valve width, together forming a lanceolate space with a tumid center somewhat offset to the ventral side of the valve. The raphe is distinctly lateral, becoming weakly reverse-lateral near the proximal and distal ends. Proximal raphe ends are offset to the ventral side and tipped with distinctly expanded central pores. Distal fissures are hooked towards the dorsal side. Striae are radiate throughout and more dense near the apices and on the ventral side. Areolae number 25-30 in 10 µm.
Cymbopleura edlundii is known only from the type locality, a small pond in Glacier National Park, Montana, near the Canadian border. Water quality data for this pond are not available.
Valves lanceolate with rounded subrostrate apices, distinctly dorsiventral in small specimens, slightly dorsiventral in larger specimens. Valve length 51–87 μm; valve width 14.3–17.9 μm. Axial and central areas very wide, 1/3 to 1/2 valve width, together forming a lanceolate space with a tumid center somewhat offset towards the ventral margin. Raphe distinctly lateral, becoming weakly reverse-lateral near proximal and distal ends. Proximal raphe ends offset to the ventral side, tipped with distinctly expanded pores. Distal raphe ends hooked towards the dorsal side. Striae radiate throughout, 9–13 in 10 μm at valve center, 14–16 in 10 μm near the apices. Areolae 25–30 in 10 μm.
Bahls, L. (2012). Cymbopleura edlundii. In Diatoms of North America. Retrieved November 17, 2024, from https://diatoms.org/species/cymbopleura_edlundii
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Cymbopleura edlundii 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.