• Category
  • Length Range
    34-67 µm
  • Width Range
    8-12 µm
  • Striae in 10 µm
    10-13 at the central portion, 14-16 at the poles



Valves trullate, with broadest portion of the valve outline located towards the footpole from the central nodule. Apices rounded. Raphe distinctly undulate, with rounded external proximal ends. The axial area is narrow, straight, expanded slightly to form a linear-ellipsoidal central area that bears a single, relatively large stigma. A longitudinal line is positioned next to, or near, the axial area. Striae are distinctly biseriate, radiate near the central area, becoming parallel then radiate at the headpole, and becoming strongly radiate at the footpole. A distinct apical pore field is present at the footpole.


Original Description

  • Author
    Kociolek and Stoermer 1988

Cite This Page

Kociolek, P. (2011). Gomphoneis eriense var. angularis. In Diatoms of North America. Retrieved May 20, 2024, from https://diatoms.org/species/gomphoneis_angularis


The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Gomphoneis eriense var. angularis 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.