Psammothidium bioretii

(Germain) Bukhtiyarova and Round 1996      Category: Monoraphid
BASIONYM: Achnanthes bioreti Germain 1957
SYNONYM(S): Achnanthes biorettii Germain 

Pleurosira laevis

 

Psammothidium chlidanos
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LM scalebar = 10 µm = 80 pixels.

Observations

Contributor: Marina Potapova - August 2010
Length Range: 12-26 µm
Width Range: 5.3-9.1 µm
Striae in 10 µm: 23-27

Description

Valves are elliptical. Both valves have narrow axial areas, which are often oblique to the apical axis and not parallel between the two valves. The central area is transversely elliptical or rectangular, bordered by 4-7 shortened striae of variable length. The raphe is straight or sigmoid near the apices, with slightly expanded terminal ends, but without terminal raphe fissures. The central raphe ends are simple or slightly expanded externally. Internally, the central raphe ends curve toward opposite sides. Striae are radiate through both valves and continue to the valve mantle, 23-27 in 10 µm in the middle and up to 30 in 10 µm at the apices. The external and internal openings of the areolae are circular, becoming transapically elongated toward the margins.

Original Description

Basionym: Achnanthes bioreti
Author: Germain 1957
Length Range: 18-20 µm
Width Range: 8-10 µm
Striae in 10 µm: 22-25

Original Description

Valva elliptica, apicibus largiter rotundatis (18-20 μm longa, 8-10 μm lata); striae omnes radiantes (22-25 in 10 μm) evidenter punctatae, aream longitudinalem angustam limitantes; area centralis secundum quadrilateram dilatata cum striis majoribus et minoribus alternatim; raphe evidenter obliquus secundum axem longitudinalem, pseudoraphe leviter obliquus.

Original Images

Cite This Page:
Potapova, M. (2010). Psammothidium bioretii. In Diatoms of the United States. Retrieved May 22, 2013, from http://westerndiatoms.colorado.edu/taxa/species/psammothidium_bioretii

Species: Psammothidium bioretii

Contributor: Marina Potapova

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Image Credit: Marina Potapova

  1. Valves elliptical
  2. Central area on both valves transversely elliptical or rectangular
  3. Axial areas and raphes oblique to the apical axis, not parallel between valves, sigmoid toward apices

Valves are elliptical. Both valves have narrow axial areas, which are often oblique to the apical axis, not parallel between the two valves, and sigmoid toward the apices. The central area is transversely elliptical or rectangular. The striae are radiate throughout .

Compare

Psammothidium bioretii differs from P. helveticum by its elliptical shape and smaller central areas. It differs from both P. helveticum and P. daonense by the non-parallel axial areas on both valves. P. daonense also has a large rhomoid axial area on the rapheless valve.

Psammothidium helveticum

Psammothidium daonense

Citations

Bukhtiyarova, L. and Round, F. E. (1996). Revision of the genus Achnanthes sensu lato. Psammothidium, a new genus based on Achnanthidium marginulatum. Diatom Research 11: 1-30.

Germain, H. (1957). Achnanthes bioreti n. sp., diatomée nouvelle. Bulletin de la Société Botanique de France 104 (suppl.):85-86.

Manoylov, K.M. (2007). On some Psammothidium species from rivers in the United States. Diatom Research 22(2): 317–327.

Links & ID's

Index Nominum Algarum (INA)

INA

California Academy of Sciences (CAS)

Psammothidium bioretii CAS

North American Diatom Ecological Database (NADED)

NADED ID: 186001

Autecology Discussion

Habits

Size Range

101-1000 µm3 (ie Amphora veneta)

Motility

slightly motile (e.g. Cocconeis)

Attachment

prostrate (e.g. mucilage pad)

Habitat

benthic

Colony

solitary

EMAP Assessment

Sampling for the Environmental Protection Agency (EPA) western Environmental Monitoring and Assessment Program (EMAP) study was completed during the years 2000-2004 (see citations at bottom of this page). Streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming). Over 1200 sites on streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming) were selected for sampling based on a stratified randomized design. This type of design insures that ecological resources are sampled in proportion to their actual geographical presence. Stratified randomized design also allows for estimates of stream length with a known confidence in several “condition classes” (good or least-disturbed, intermediately-disturbed, and poor or most-disturbed) for biotic condition, chemistry and habitat.

EMAP Distribution

Psammothidium bioretii

Distribution

The distribution map represents the relative abundance of this Psammothidium bioretii in the western EMAP study. Relative abundance is a measure of the proportion of cells of this species based on a "fixed count" of 300 total diatom cells counted and identified. Each of the western EMAP sample sites is shown, either with a black dot for sites where Psammothidium bioretii was not recorded, or with a red circle indicating the relative abundance of Psammothidium bioretii.

Note that the size of the proportional symbols varies between species to help show both abundant and rare species.

Scale for the map to the left

EMAP Response Plots

Psammothidium bioretii

Responses

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

EMAP citations

Results are published in:

Johnson, T., Hermann, K., Spaulding, S., Beyea, B., Theel, C., Sada, R., Bollman, W., Bowman, J., Larsen, A., Vining, K., Ostermiller, J., Petersen, D. Hargett, E. and Zumberge, J. (2009). An ecological assessment of USEPA Region 8 streams and rivers. U.S. Environmental Protection Agency Region 8 Report, 178 p.

Stoddard, J. L., Peck, D. V., Olsen, A. R., Larsen, D. P., Van Sickle, J., Hawkins, C. P., Hughes, R. M., Whittier, T. R., Lomnicky, G. A., Herlihy, A. T., Kaufman, P. R., Peterson, S. A., Ringold, P. L., Paulsen, S. G., and Blair, R. (2005). Environmental Monitoring and Assessment Program (EMAP) western streams and rivers statistical summary. U.S. Environmental Protection Agency Report 620/R-05/006, 1,762 p.

Stoddard, J. L., Peck, D. V., Paulsen, S. G., Van Sickle, J., Hawkins, C. P., Herlihy, A. T., Hughes, R. M., Kaufman, P. R., Larsen, D. P., Lomnicky, G. A., Olsen, A. R., Peterson, S. A., Ringold, P. L., and Whittier, T. R. (2005). An ecological assessment of western streams and rivers. U.S. Environmental Protection Agency Report 620/R-05/005, 49 p.