• Category
  • Length Range
    35-70 µm
  • Width Range
    6-7 µm
  • Striae in 10 µm



Valves are linear with slightly protracted ends. Axial area is narrow. Central area is moderately asymmetrical, wedge-shaped or irregularly shaped. The central area is larger on the primary side, and semi-elliptical and smaller on the secondary side, but in some specimens it may be nearly symmetrical. Central raphe endings are slightly expanded. Striae are radiate at the central valve, convergent near the apices. Striae are 11-12 in 10 µm. Areolae are lineolate, with approximately 32 in 10 µm.

Original Description

Navicula a latere secundo anguste lanceolata, apicibus obsolete productis, nodulo centrali oblongo, striis obscure punctatis radiantibus 32 in 0.001'". Longitud. 0.0020-0.0017", latid. 0.0002-0.00023".

  • Author
    Grunow 1860
  • Length Range
    43-51 µm
  • Width
    5.1-5.8 µm
  • Striae in 10µm

Original Images

Naangusta  Or Ill001
Naangusta  Or Descr001

Citations & Links

Cite This Page

Potapova, M. (2011). Navicula angusta. In Diatoms of North America. Retrieved May 24, 2024, from https://diatoms.org/species/navicula_angusta


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