Valves are elliptical-lanceolate with subrostrate ends, 5.0-7.5 µm wide and 11-23 µm long. The raphe is straight and filiform. The axial area is narrow and linear. The central area is small, without isolated areolae. Striae are uniseriate, radiate, and number 16-23 in 10 µm. Areolae are apically elongated and number approximately 65-70 in 10 µm. Subpolar areolae, or annulae, are larger than areolae on other parts of the valve. The annulae form three-four rows at each pole. Note that North American specimens have slightly more drawn-out valve apices than European specimens. This morphological difference may indicate that North American “G. kriegeri” is another species.
Schalen elliptisch bis lanzettlich-elliptisch mit breit gerundeten Enden. 14—19 μ lang, 6—7 μ breit. Area sehr eng, in der Mitte kaum erweitert. Streifen wenig radial, etwa 16 in 10 μ, nach den Enden enger.
Potapova, M. (2010). Geissleria kriegeri. In Diatoms of North America. Retrieved November 23, 2024, from https://diatoms.org/species/geissleria_kriegeri
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Geissleria kriegeri 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.