• Category
  • Length Range
    36.7-55.9 µm
  • Width Range
    12.8-13.2 µm
  • Striae in 10 µm
  • Synonyms
    Gomphonema augur var. sphaerophorum Lange-Bert.
    Gomphoneis sphaerophorum Temp. and H.Perag.



Valves are clavate with a distinctly capitate headpole and a narrow footpole. Axial area is narrow, becoming linear-lanceolate in smaller specimens. Central area is transversally elliptic and incomplete. A stigma is present opposite a single shortened stria. The raphe is undulate and lateral. Striae are nearly parallel mid-valve, becoming radiate at the apices. Areolae are distinctly punctate and visible in LM, measuring 25-27 in 10 µm. A distinct porefield is present at the footpole.


Original Description

  1. ___________ sphaerophorum: G. parvum, testula subtiliter striata a dorso clavata, mucrone apicis capitato (sphaerophoro). Longitudo testulae 1/58'''. Vivum in Niagara, fossile ad Farmington.
  • Author
    Ehrenb. 1845

Original Images

G Sphaerophorum Orgidesc

Cite This Page

Polaskey, M., Bishop, I. (2016). Gomphonema sphaerophorum. In Diatoms of North America. Retrieved July 19, 2024, from https://diatoms.org/species/gomphonema_augur_var._sphaerophorum


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