Valves are weakly silicified and narrow linear-lanceolate with acutely pointed apices. The axial area is very narrow and barely wider than the raphe. The central area is absent. Raphe branches are filiform. Proximal raphe ends are straight, not expanded, and very close together. Striae are finely lineate and weakly radiate throughout. Areolae in the striae number about 45 in 10 µm.
Note: the name Navicula duerrenbergiana is considered to be invalid (California Academy of Sciences, Catalogue of Diatom Names, September 2011).
There are 101 records of Navicula duerrenbergiana in the Montana Diatom Collection, all of them from streams on the Northwestern Great Plains of Montana, South Dakota, and Wyoming. These waters have a mean pH of 8.2 and a mean conductivity of 1899 µS/cm, along with elevated concentrations of sodium and sulfate (see table below). Common diatom associates of Navicula duerrenbergiana in these habitats include Mastogloia smithii, Nitzschia reversa, Gyrosigma macrum, Mastogloia elliptica, Nitzschia microcephala, Tryblionella compressa, Nitzschia filiformis, Navicula salinicola, Diploneis puella, and Biremis circumtexta. In Europe, Krammer and Lange-Bertalot (1986) report Navicula duerrenbergiana from brackish waters along sea coasts and from inland waters with elevated electrolyte content.
Bahls, L. (2012). Navicula duerrenbergiana. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/navicula_duerrenbergiana
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Navicula duerrenbergiana 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.