• Category
  • Length Range
    13.5-26.3 µm
  • Width Range
    3.7-4.6 µm
  • Striae in 10 µm
    18-20 at the valve center, 20-22 at the ends

Identification

Description

Valves are small, narrow and linear, with subrostrate ends. The axial area is narrow. The stauros is bow-tie shaped, commonly with areola present at the valve margins. The raphe is filiform and straight, with weakly inflated proximal ends and unilaterally curved distal ends. Striae are weakly radiate near the valve center, numbering 18-20 in 10 µm. Striae are weakly radiate to parallel at the apices, numbering 20-22 in 10 µm. The striae are composed of areolae numbering 27-29 in 10 µm. Pseudosepta are present.

Autecology

Stauroneis bovbjergii is a taxon only reported from the Excelsior Fen-complex located on the Dugout Creek Wildlife Management Area, Dickinson County, Iowa (Reimer 1990). The Excelsior Fen-complex is an alkali fen, influenced by row-crop agriculture (Reimer 1982) .

Sampling  Excelsior  Fen
Credit: David Burge
Ecology and Systematics of Diatoms course students sampling algal mats at Excelsior Fen.

Original Description

Valve linear with slightly convex margins and protracted sub-rostrate to rostrate ends. Stauros across valve center and a pseudosepum at each apex. Axial area narrow linear. Central area quadrangular with one or two short striae at the margins. Raphe filiform; proximal raphe ends blunt, distal ends curved slightly in the same direction. Striae radiate becoming mostly parallel, sometimes slightly convergent, at the ends; indistinctly punctate. Length 14-25 um. Width 4-4.5 um. Striae 18-20 in 10 um becoming ca. 22 in the 10 um at ends. Puncta ca. 25-27 in 10 um.

Holotype: ILL #SP 7. Iowa, Dickinson Co., Excelsior Fen # 11. "S. edge of S. knob; in Scirpus shade on moss." Coll: R.L. Mitchem, July 25, 1972.

  • Author
    Reimer 1990
  • Length Range
    14-26 µm
  • Width
    4-4.5 µm
  • Striae in 10µm
    18-20 in the center valve, 22 at the ends

Original Images

Stbovbjergii Original Image
Stbovbjergii Original Text

Cite This Page

Burge, D, and Edlund, M. (2016). Stauroneis bovbjergii. In Diatoms of North America. Retrieved August 18, 2018, from https://diatoms.org/species/stauroneis_bovbjergii

Responses

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