Valves are lanceolate with rather narrow, obtusely rounded ends that are slightly protracted. The axial area is narrow, widening slightly near the transverse, irregular central area. The raphe is moderately lateral, with inflated proximal ends that are deflected slightly toward the primary side. Striae are radiate and more widely spaced in the central area, becoming convergent at the ends. Areolae are coarse, consistently numbering 20 in 10 µm.
There are four records of Navicula vaneei in the Montana Diatom Collection, from Freshwater Creek in California and Big Sandy and Squirrel Creeks in Montana. Concurrent water chemistry data for these samples suggest that N. vaneei prefers fresh calcium-bicarbonate waters of moderate conductivity. Lange-Bertalot (2001) reports Navicula vaneei from Europe and northwestern Siberia, where it prefers waters with average to high electrolyte content. Common diatom associates of N. vaneei in the western U.S. include Psammothidium ventralis, Navicula integra, Diploneis subovalis, Nitzschia valdecostata, Tryblionella littoralis, Nitzschia tubicola, Cymbella aspera, Placoneis constans, Planothidium engelbrechtii, Navicula streckerae, Navicula pseudotenelloides, Denticula subtilis, Stauroneis phoenicenteron, Cylindrotheca closterium, Karayevia oblongella, Anomoeoneis sphaerophora, and Navicula peregrina.
Valves lanceolate with ends which are regularly not protracted or exceptionally indistinctly protracted, apices obtusely rounded, 40-80 microns long, 11-13 microns broad. Raphe fissures moderately lateral with coarsely marked central pores. Axial area linear and moderately narrow, central area distinctly asymmetric, transversely rectangular to elliptic. Transapical sstriae radiate, convergent at the apices, 8-10 in 10 microns. Lineolae comparatively coarse, 20-24 in 10 microns. SEM: The large central pores with short, hook-like processes are similar to N. peregrina.
Bahls, L. (2011). Navicula vaneei. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/navicula_vaneei
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Navicula vaneei 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.