Valves are elliptical-lanceolate with short, rostrate, narrowly round apices. Fibulae small, but distinct, 14-16 in 10 µm. Striae are punctate and resolvable with LM.
Krammer and Lange-Bertalot (1988) note that the central two fibulae are equidistant from one another, but this is not evident in the US populations. North American populations are more narrow than indicated by Krammer and Lange-Bertalot.
Kociolek, P. (2011). Nitzschia desertorum. In Diatoms of North America. Retrieved October 10, 2024, from https://diatoms.org/species/nitzschia_desertorum
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Nitzschia desertorum 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.