• Category
  • Length Range
    58.6-77.0 µm
  • Width Range
    21.3-26.4 µm
  • Striae in 10 µm
    15-17

Identification

Description

Valves are elliptical to elliptical lanceolate, with capitate apices. The axial area is broad and expanded to form a large lanceolate rhombic central area. The central area is slightly asymmetric from one side of the axial area to the other. The raphe is straight and centrally located. Proximal raphe ends are slightly expanded. Distal raphe ends are curved in the same direction. Striae radiate throughout most of the valve, becoming parallel to convergent at the ends. Two longitudinal lines are present along each side of the raphe, dividing the striae approximately into thirds.

Note that Patrick and Reimer (1966) report a greater range in length (36-80 µm) and breadth (20-30 µm).

Autecology

Caloneis amphisbaena was found in epipelon samples from the Little Sioux River, Dickinson County, Iowa. Other specimens were found in epiphytic samples from Dugout Creek, Dickinson County, Iowa.

Mann (1989) stated that Caloneis amphisbaena in Blackford Pond appeared to be asexual, as no cells were observed to pair and form auxospores.

Image0094And0100 Cropped
Credit: Jaime Haueter
Caloneis amphisbaena live cell in valve view and girdle view.
Image0088 Cropped
Credit: Jaime Haueter
Caloneis amphisbaena live cell in valve view showing chloroplast structure.
Image0108 Cropped
Credit: Jaime Haueter
Caloneis amphisbaena live cell in valve view showing chloroplast structure.
Img 1063
Credit: Viviana Mazzei
Sampling Caloneis amphisbaena from epipelon of Little Sioux River, Dickinson County IA

Original Description

  • Basionym
    Navicula amphisbaena
  • Author
    Bory 1824

Original Images

Navicula amphisbaena orig illus

EMAP Assessment

EMAP Distribution

Caloneis Amphisbaena   Bory   Cleve 20
Map 20

Response Plots

Caloneis Amphisbaena

Cite This Page

Haueter, J. (2014). Caloneis amphisbaena. In Diatoms of North America. Retrieved July 21, 2018, from https://diatoms.org/species/caloneis_amphisbaena

Responses

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