Diatoms of North AmericaDiatoms of North America

Geissleria ignota

(Krasske) Lange-Bert. and Metzeltin 1996

Geissleria Ignota Guide
  • Category
    Symmetric Biraphid
  • Length Range
    16-18 µm
  • Width Range
    3.0-3.2 µm
  • Striae in 10 µm
    15-16

Identification

Geissleria ignota LM6 Geissleria ignota LM5 Geissleria ignota LM2 Geissleria ignota LM3 Geissleria ignota LM4 Geissleria ignota LM1
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Description

Valves are triundulate with rostrate to subcapitate ends. The central area is expanded laterally with 2-4 shortened striae at the valve margin. The striae are radiate near the center of the valve becoming parallel near the ends. Two to three rows of annulae are at each apex of the valve.

Autecology

Original Description

Linear, dreiwellig, Enden gerundet. Lang 17-25µ, breit 4,5-5µ. 12-14 Streifen in 10 µ, gebogen, die konvexe Seite den Enden zugewandt, die mittelsten stark verkürzt, so daB sich die schmale, lineare Längsarea in der Mitte fast bis zum Rande erweitert. Die mittleren Streifen konvergierend , gegen die Enden senkrecht zur Raphe.

  • Basionym
    Navicula ignota
  • Author
    Krasske 1932
  • Length Range
    17-25 µm
  • Width
    4.5-5 µm
  • Striae in 10µm
    12-14

Original Images

Gignota Orig Ill
Gignota Orig Descr

Cite This Page

Lowe, R. (2011). Geissleria ignota. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/geisleria_ignota

Responses

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