• Category
  • Length Range
    14-18 µm
  • Width Range
    6.5-7.5 µm
  • Striae in 10 µm
  • Synonyms
    Navicula confervacea (Kütz.) Grunow in Van Heurck 1880



Valves are elliptical with apices protracted in larger specimens. Central area broad and rounded, continuing into the axial area, which tapers toward the ends. There is a rounded central nodule visible when focusing on the interior of the valve. The raphe is straight and filiform and may be missing due to secondary filling during silicification. The striae are radiate, punctate, crossed by longitudinal wavy lines, and of variable length.

This species is typically found in quiescent waters living in chains aligned valve face to valve face.

Original Description

DIADESMIS CONFERVACEA. Taf. 30. Fig. 8. (420/1). D. laevis articulata, articulis diametro duplo brevioribus, altero latere lanceolatis, utrinque acuminatis acutis. Long. (Navicularum) Unter Conferven aus dem „River Maraval" der Insel Trinidad: Krüger! (Herb, Sonder.)

  • Author
    Kütz. 1844

Original Images

Diadesmis confervacea orig illus
Diadesmis Confervacea  Descr

EMAP Assessment

EMAP Distribution

Diadesmis Confervacea 40 Copy
Map 40

Response Plots

Diadesmis Confervacea Copy

Cite This Page

Kociolek, P. (2011). Diadesmis confervacea. In Diatoms of North America. Retrieved July 20, 2019, from https://diatoms.org/species/diadesmis_confervacea


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