Valves are acuminate-apiculate. A small, acute to blunt protracted headpole is present, while the footpole is rounded. The broadest portion of the valve is near the headpole and/or the central portion of the valve. This feature appears to be population-dependent. Initial valves lack the acuminate structure and appear rounded at the poles and tumid in the middle. The axial area is straight, forming a transverse central area. The striae about the central area are more separate from one another. On one side of the central area there is a shortened stria, on the opposite side the central stria terminates at the stigma. The raphe is lateral and undulate. The punctate striae are radiate about the center, becoming parallel toward the poles returning to radiate at the headpole and strongly radiate towards the footpole.
Kociolek, P. (2011). Gomphonema coronatum. In Diatoms of North America. Retrieved November 23, 2024, from https://diatoms.org/species/gomphonema_coronatum
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Gomphonema coronatum 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.