Valves are lanceolate with slightly rostrate, rounded ends, 8-10 µm wide by 28-44 µm long. The raphe is filiform. The central portions of the raphe branches and proximal raphe ends are deflected toward the primary side. Terminal raphe fissures are hooked towards the secondary side. The axial area is narrow and linear. The central area is oval to slightly asymmetrical. Striae are strongly radiate, becoming slightly convergent at the valve apices. Striae are lineolate, 12 in 10 µm. Areolae are 30-32 in 10 µm.


Original Description

Frustula e facie connectivali linearis , ad utrumque finem parum attenuata, apicibus truncatus.Valvae lanceolatae, 25-65 um longae, 8-12.5 latae, apicibus plus minus sed leniter attenuato-rostratis; striis transversis circa nodulum medianum abbreviatis et aream hyalinam fere rotundatam circum eumlinquentibus, usque fere ad apices valvae radiantibus, subtiliter lineolatis (circiter 35 linolae in 10 um) in valvae medio 10-11, ad apices13-15 in 10 um. Rami raphe directi poris centralibus distinctibus fissurisque terminalibus brevibus unilateraliter curvatis. Holotypus: Sub no. 708 (=Herbarium Kützing 874) in collectione Grunow in Vindisbona (Wein). Isotypus sub no. BM 18712 in collectione Kützing in London (British Museum). Habitat: In aqua dulci prope urbem Carlsruhe, Germania, ceterum passim in aquis dulcibus et subsalsis diversis in Europa et America frequentissime adest.

  • Author
    Lange-Bert. 1980
  • Length Range
    25-65 µm
  • Width
    8-12.5 µm
  • Striae in 10µm
    10-11 (median), 13-15 (polar)

Original Images

Natrivialis  Ill
Natrivialis  Descr

EMAP Assessment

EMAP Distribution

Navicula Cryptocephala 40 Copy
Map 40

Response Plots

Navicula Cryptocephala Copy

Cite This Page

Rushforth, S, and Spaulding, S. (2010). Navicula trivialis. In Diatoms of North America. Retrieved June 17, 2018, from


The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Navicula trivialis 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.