Diatoms of North AmericaDiatoms of North America

Psammothidium sacculus

(J.R. Carter) Bukhtiyarova 1996

Psammothidium sacculum guide
  • Category
    Monoraphid
  • Length Range
    8-13 µm
  • Width Range
    3.9-4.4 µm
  • Striae in 10 µm
    26-30
  • Synonyms
    Achnanthes saccula J.R. Carter 1981

Identification

Psammothidium sacculum LM5 Psammothidium sacculum LM3 Psammothidium sacculum LM4 Psammothidium sacculum LM6 Psammothidium sacculum LM2 Psammothidium sacculum LM7 Psammothidium sacculum LM1
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Description

Valves are elliptic to linear-elliptic. The raphe valve has a narrow linear axial area and a transversely rectangular or bow-tie shaped central area bordered by a few striae of various lengths. The raphe is straight, without terminal fissures with simple and very slightly expanded distal and proximal ends.  The central raphe ends curve toward opposite sides internally. The rapheless valve has a narrow rhomboid axial area, which  widens in the valve center into small and often asymmetric central area. Striae are radiate on both valves. Areolae are visible in LM.

Autecology

This taxon has been mostly reported from colder regions of Northern Hemisphere. Specimens illustrated on this page are from collections in sites in Alaska.

Original Description

  • Basionym
    Achnanthes saccula
  • Author
    J.R.Carter 1981
  • Length Range
    10 µm
  • Width
    4 µm
  • Striae in 10µm
    30-32

Original Images

Psammothidium sacculum Orig Ill
Psammothidium sacculum Orig Descr

Updates

Oct 31, 2024 - Correction of specific epithet

From 8/26/2024 until 10/31/2024, this taxon appeared as Psammothidium sacculum. As of 10/31/2024, the ending is corrected to "sacculus" to match the Latin ending for a noun, rather than an adjective. - S. Spaulding

Cite This Page

Potapova, M. (2024). Psammothidium sacculus. In Diatoms of North America. Retrieved November 12, 2024, from https://diatoms.org/species/psammothidium-sacculus

Responses

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