• Category
  • Length Range
    20.5-36.0 µm
  • Width Range
    7.5-8.0 µm
  • Striae in 10 µm



Valves are linear-elliptical with bluntly rounded ends. The axial area is very narrow, linear almost indistinguishable with a small quadrate to slightly rectangular central area, 1.3–1.6 μm wide. The longitudinal canal is linear with undistinguishable number of areolae under LM. The raphe is linear with slightly expanded proximal ends. The striae are parallel to slightly radiate with undistinguishable number of areolae under LM.

This taxon has been included within D. marginstriata Hust., the broad sense, in many surveys.


This taxon is not common, but widely distributed in lakes of the northeast U.S. Images on this page are from lakes in Maine (Little Lake, Little Watchic Lake, an unnamed lake shore), New Jersey (Panther Lake), and Massachusetts (Lower Spectacle Pond).

Original Description

Valves of both taxa linear-elliptical with broadly rounded ends. Length 16–27 (vs. 18–40 in D. marginestriata) μm, breadth 7–9 (vs. 8–11) μm; ratio length- to-breadth 2.3–2.9 (vs. 2.2–3.6) Zone of the canals 3–4 (vs. 3–6) μm broad. Striae 18–20, on average 19, (vs. 17–18) in 10 μm. Thus the maximum length of examined specimens of D. galloprovincialis is distinctly smaller, breadth of valves and canal systems is moderately smaller, and stria density is higher than in D. marginestriata.

Fine-structural characteristics that separate the two taxa are discernible in external SEM view as follows (see Figs 171: 1–4 vs. Figs 164: 13–15; 165: 1–4). First, the adaxial areolae are prolonged transapically in subproximal and sub- distal parts of the canals only in D. galloprovincialis; they are isodiametrically compact in D. marginestriata. Secondly, in D. marginestriata sinuous openings and volate structures are simple rather than complicatedly branching as in D. galloprovincialis (Figs 164: 14, 15 vs. Figs 171: 1–3). Thirdly, unlike D. gallo- provincialis, D. marginestriata exhibits little warts (pustules) that are irregularly distributed over the external wall (Fig. 164: 14). Larger unstructured openings on either side across the external wall into the canals are absent from both taxa.

  • Author
    Lange-Bert., Fuhrmann and V. Peeters 2020
  • Length Range
    16–27 µm
  • Width
    7–9 µm
  • Striae in 10µm

Original Images

Diploneis galloprovincialis Orig Illus
Diploneis galloprovincialis Orig Desc

Cite This Page

Jovanovska, E., Phillips, N., Polaskey, M. (2021). Diploneis galloprovincialis. In Diatoms of North America. Retrieved July 15, 2024, from https://diatoms.org/species/diploneis-galloprovincialis


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