Identification

Description

Valves are linear to linear-elliptic with convex to nearly parallel sides, narrowing to rostrate to capitate apices. Pseudosepta are present but positioned very near the valve ends. Raphe branches are filiform and straight. Proximal raphe ends are straight and slightly inflated. The axial area is narrow and linear, and typically bordered on each side by an uninterrupted longitudinal row of areolae. The central area is a rectangular stauros, sometimes oriented somewhat obliquely. Striae are parallel at the center, becoming weakly radiate towards the apices. Areolae are coarse, transversely oblong, and irregularly spaced and number 12-16 in 10 µm.

Autecology

Stauroneis lauenburgiana has been found in several lakes, ponds, marshes, and spring pools in Glacier National Park, Waterton Lakes National Park, and elsewhere in the Northern Rockies, but nowhere is it found in abundance. The pH of these waters ranges from 6.1 to 8.6 and specific conductance ranges from 75 to 332 µS/cm. Hustedt (1950) described this species from lakes in northern Germany.

Spring Pool On Trail Between  Kintla  Lakes
Credit: Mike Pasichnyk
Pool on trail near Kintla Lake, Glacier National Park, Montana: home of Placoneis abiskoensis.

Original Description

  • Author
    Hust. 1950
  • Length Range
    32-40 µm
  • Width
    10-11 µm
  • Striae in 10µm
    18-21

Original Images

Stauroneis Lauenburgiana  Orig Ill
Stauroneis Lauenburgiana  Orig Descr

Cite This Page

Bahls, L. (2011). Stauroneis lauenburgiana. In Diatoms of North America. Retrieved July 22, 2018, from https://diatoms.org/species/stauroneis_lauenburgiana

Responses

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