• Category
  • Length Range
    17-57 µm
  • Width Range
    8.1-12.8 µm
  • Striae in 10 µm



Valves are elliptical to linear-elliptical with convex to nearly parallel sides and blunt, obtusely rounded apices. The axial area is narrow, barely wider than the raphe, and the central area is circular. Raphe branches are lateral and sinuous, with weakly expanded proximal ends. Partecta are numerous and all about the same size. Striae consist of single rows of areolae and are radiate throughout. Areolae are coarse and number 16-20 in 10 µm.


There are 156 records of Mastogloia elliptica in the Montana Diatom Collection, nearly all of them from streams on the Northwestern Great Plains. The mean electrical conductivity of these waters is 3824 μS/cm, mean chloride is 83 mg/L, and mean pH is 8.6. However, in some of these waters such as Salt Creek in Wyoming, conductivity may range up to 45700 μS/cm and chloride content up to 13200 mg/L. Common diatom associates of M. elliptica on the Great Plains include Cymbella pusilla, Mastogloia smithii, Nitzschia microcephala, Navicula peregrina, Tabularia fasciculata, Amphora coffeaeformis, Entomoneis paludosa, and Ctenophora pulchella. Patrick and Reimer (1986) report M. elliptica as a halophilic to mesohalobic taxon characteristic of coastal areas, but also found in inland lakes with some salinity. In Europe, Krammer and Lange-Bertalot (1986) report M. elliptica from brackish waters in coastal areas and from saline inland waters.

Sb Below  Salt  Ds
Credit: Photo courtesy Wyoming DEQ.
Stockade Beaver Creek below Salt Creek, Weston County, Wyoming: home of Mastogloia elliptica.

Original Description

  • Basionym
    Frustulia elliptica
  • Author
    C.Agardh 1824

Original Images

Maselliptica Origimag
Mastogloia Elliptica  Orig Descr

Cite This Page

Bahls, L. (2012). Mastogloia elliptica. In Diatoms of North America. Retrieved June 19, 2024, from https://diatoms.org/species/mastogloia_elliptica


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