• Category
  • Length Range
    11.7-20.1 µm
  • Width Range
    2.2-3.7 at the valve center, 6.3-8.4 at the widest part of the valve µm
  • Striae in 10 µm
    16-18 at center valve
  • Synonyms
    Tabellaria binalis (Ehrenb.) Grunow



Valves are small and panduriform with a flat valve face. The apices are rounded in larger valves, becoming more broad in smaller valves. A central sternum is faintly evident. Striae are parallel at the valve center, becoming curved and convergent at the apical inflations, finally becoming slightly radiate at the apices. Copulae number 6 to 8 in 10 µm (girdle view), each with a septum at the end opposite the open end of the girdle band. Each valve has a single rimoportula located near one of the apical pore fields, not visible in LM.


Oxyneis binalis can form ribbon-like or zigzag colonies by attachment at the apical pore fields with mucilage pads. Oxyneis binalis has been reported from the northeastern United States and often occurs in lakes with low pH (Lewis 1865, Flower 1989, Camburn and Charles 2000, Siver and Hamilton 2011).

Oxyneis Binalis Lower48
Credit: USGS BioData & GoogleEarth
Distribution of Oxyneis binalis in rivers of the continental U.S. based on the National Water Quality Assessment program. Retrieved 13 June 2016.

Original Description

  • Basionym
    Fragilaria binalis
  • Author
    Ehrenb. 1854

Original Images

Fragilaria binalis orig illus
Frbinalis Original Text2

Cite This Page

Burge, D, and Edlund, M. (2016). Oxyneis binalis. In Diatoms of North America. Retrieved July 22, 2018, from https://diatoms.org/species/oxyneis_binalis


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