• Category
  • Length Range
    6-16 µm
  • Width Range
    2.5-4 µm
  • Striae in 10 µm
  • Synonyms
    Amphora ovalis var. pediculus (Kütz.) Van Heurck 1885



Valves moderately dorsiventral, semi-elliptical becoming semi-circular in small taxa. Dorsal margin arched, ventral margin straight to slightly concave. Valve ends rounded, sometimes with a slight ventral deflection. Axial area very narrow with the raphe ledge poorly developed. Raphe straight with proximal raphe ends straight and distal raphe ends dorsally deflected. Dorsal and ventral fascia distinct and extending to valve margins. Dorsal striae parallel in central area, becoming weakly radiate at the apices. Dorsal striae distinctly punctate with 2-3 rows of areolae near the central area. Ventral striae composed of a single row of areolae, radiate near the central area, becoming convergent at the apices.

Schoeman and Archibald (1978) in an examination of A. perpusilla based on slide BM 26315 concluded that A. perpusilla was identical to their concept of A. pediculus (the concept adopted here), and therefore will be considered synonyms. Due to their small size the light microscope may be inadequate to describe the diversity of this group, further revision is probably needed (see Lee & Round (1989), Krammer (1980) and Schoeman & Archibald (1978) for a more thorough discussion).

Original Description

  • Basionym
    Cymbella pediculus
  • Author
    Kütz. 1844

Original Images

Cymbella pediculus orig illus
Cymbella pediculus orig descr

Cite This Page

Stepanek, J., Kociolek, P. (2011). Amphora pediculus. In Diatoms of North America. Retrieved May 18, 2024, from https://diatoms.org/species/amphora_pediculus


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