• Category
  • Length Range
    15.0-17.3 µm
  • Width Range
    5.6-6.0 µm
  • Striae in 10 µm



Valves ovate with broadly rounded ends, and may contain a slight bilateral central inflation. Striae are weakly radiate and curved, increasingly so toward the apices. The central area small and circular, encompassed by somewhat shortened marginal striae. A robust, linear conopeum covers the middle half of the valve and obscures the axial area. The raphe is filiform with inflated proximal and distal ends. Distal ends are inflated unilaterally deflected. Areolae not visible in LM.

Original Description

  • Basionym
    Navicula subhamulata
  • Author
    Grunow 1880

Original Images

Nav Subhamulata Orig Desc Plate
Nav Subhamulata Orig Desc Text

Cite This Page

Bishop, I. (2016). Fallacia subhamulata. In Diatoms of North America. Retrieved April 16, 2024, from https://diatoms.org/species/fallacia_subhamulata


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