• Category
  • Length Range
    32-60 µm
  • Width Range
    6–10 µm
  • Striae in 10 µm



Valves are linear-lanceolate with wedge-shaped ends, 6-10 µm wide, 32-60 µm long. The raphe is straight. The axial area is narrow, linear, with the central area transversely rectangular or elliptical. The striae are almost parallel throughout the valve, weakly radiate in the middle and slightly convergent at the apices, 9-12 in 10 µm. Areolae 30-33 in 10 µm.


Eutraphentic species

Original Description

Vibrio linearis, utrique attenuatus, globulis tribus, extremis minoribus.

  • Basionym
    Vibrio tripunctatus
  • Author
    O.F.Müll. 1786

Original Images

Nav Trip  Orig Illustr
Nav Trip  Orig Descr

EMAP Assessment

EMAP Distribution

N Tripunctatum 10
Map 10

Response Plots

Navicula Tripunctata

Cite This Page

Potapova, M. (2009). Navicula tripunctata. In Diatoms of North America. Retrieved June 23, 2018, from https://diatoms.org/species/navicula_tripunctata


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