• Category
  • Length Range
    30-37 µm
  • Width Range
    7.0-7.7 µm
  • Striae in 10 µm
  • Reported As
    Navicula salinarum var. intermedia (Patrick and Reimer 1966)



Valves are lanceolate, with protracted rostrate ends, 7.0-7.7 µm wide and 30-37 µm long. The raphe is filiform. The axial area is narrow and linear. The central area is oval to irregular, often with alternately long and short striae. Striae are radiate and curved, or irregularly curved near the valve center. Striae become convergent at the valve apices. Striae are lineolate, 14-15 in 10 µm.


This taxon is broadly distributed in rivers of the US. In the EPA Western EMAP survey, it was found across a wide range of chemical and physical settings.

Original Description

N. CRYPTOCEPHALA Kg. VAR INTERMEDIA (se rapprochant du N. salinarum).

  • Basionym
    Navicula cryptocephala var. intermedia
  • Author
    Grunow in Van Heurck 1880

Original Images

Nacrypto Interm  Ill
Nacrypto Interm Text

Cite This Page

Rushforth, S., Spaulding, S. (2010). Navicula capitatoradiata. In Diatoms of North America. Retrieved May 20, 2024, from https://diatoms.org/species/navicula_capitatoradiata


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