Nitzschia amphibia

Grunow 1862      Category: Nitzschioid
SYNONYM(S): Homoeocladia amphibia (Grunow) Kuntze 1898 | Bacillaria amphibia (Grunow) Elmore in Barbour 1895 

Nitzschia alpina

 

Nitzschia angustata
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LM scalebar = 10 µm = 80 pixels.

Observations

Contributor: Pat Kociolek - March 2011
Length Range: 14-37 µm
Width Range: 4.0-4.5 µm
Striae in 10 µm: 14-18

Description

Valves are linear to lanceolate. The valves taper to bluntly rounded apices. Fibulae are distinct and number 7-9 in 10 µm. The central nodule is evident. Striae are characteristically prominent and distinctly punctate, but not necessarily regularly spaced.

Original Description

Basionym:
Author: Grunow 1862
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Kociolek, P. (2011). Nitzschia amphibia. In Diatoms of the United States. Retrieved April 25, 2018, from http://westerndiatoms.colorado.edu/taxa/species/nitzschia_amphibia

Species: Nitzschia amphibia

Contributor: Pat Kociolek

Reviewer: Rex Lowe

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Image Credit: Pat Kociolek

  1. Valves are linear to lanceolate
  2. Striae distinctly punctate
  3. Central nodule present

Valves taper to bluntly rounded apices. Fibulae are distinct, 7-9 in 10 µm. The central nodule, evident as a wider space between two central fibulae, is present. Striae are characteristically prominent and distinctly punctate, and may be irregularly spaced.

Compare

The distinctly punctate striae are characteristic of this species and differentiate it from N. alpina. Nitzschia amphibia is often found in the same habitats as N. amphibioides and is of similar size and shape. However, N. amphibia lacks the thickened fibulae that are characteristic of N. amphibioides. Furthermore, N. amphibia has a prominent central nodule, which N. amphibioides lacks.

Nitzschia alpina

Nitzschia semirobusta

Citations

Krammer, K. and Lange-Bertalot, H. (1988). Bacillariophyceae. 2. Teil: Bacillariaceae, Epithemiaceae, Surirellaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Susswasserflora von Mitteleuropa, Band 2/2. Gustav Fisher Verlag, Jena.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Nitzschia amphibia CAS

NCBI Genbank Taxonomy

Nitzschia amphibia NCBI

North American Diatom Ecological Database (NADED)

NADED ID: 48004

Autecology Discussion

Habits

Size Range

101-1000 µm3 (ie Amphora veneta)

Motility

moderately motile (e.g. Navicula tripunctata)

Attachment

prostrate (e.g. mucilage pad)

Habitat

benthic

Colony

solitary

EMAP Assessment

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). Over 1200 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

Nitzschia amphibia

Distribution

The distribution map represents the relative abundance of this Nitzschia amphibia 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 Nitzschia amphibia was not recorded, or with a red circle indicating the relative abundance of Nitzschia amphibia.

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

Nitzschia amphibia

Responses

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