Valves are elliptical with broadly rounded ends. The axial area is narrow and the central area is transverse, formed by alternating short and long striae. The raphe is filiform and the raphe branches are nearly straight. Proximal raphe ends are straight, small and bulbous. The striae are wide and radiate, becoming nearly parallel at the ends. Areolae in the striae are coarse (23-24 in 10 microns) and easily distinguished in LM.
Navicula reinhardtii has been collected from seven locations in the Northwest, all of them lakes or rivers below lakes and reservoirs. Four of these collections are from Montana with one each from Alberta, North Dakota, and South Dakota. The pH of these waters is 8.30-8.58 and specific conductance is 122-487 µS/cm. Patrick and Reimer (1966) report this species as widely distributed in fresh water of high mineral content or in slightly brackish water. Populations of Navicula reinhardtii are composed of low numbers of individuals.
Bahls, L. (2011). Navicula reinhardtii. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/navicula_reinhardtii
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Navicula reinhardtii 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.