Bacillaria paradoxa

Gmelin 1788      Category: Nitzschioid
BASIONYM: Bacillaria paradoxa Gmelin 1788

Aulacoseira valida

 

Biremis circumtexta
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LM scalebar = 10 µm = 40 pixels.

Observations

Contributor: Pat Kociolek - March 2011
Length Range: 68-102 µm
Width Range: 5.5-6.5 µm
Striae in 10 µm: 19-24

Description

Living cells occur in long chains, connected along their keels. Valves are isopolar, linear to linear-lanceolate and sometimes with slightly undulate margins tapering to narrow apices. The characteristic placement of the keel in the center of the valve distinguishes this genus from others in the Bacillariales. Keel puncta are rectangular, but not regular in shape and number about 6-10 in 10 µm. Striae are distinct, parallel, perpendicular to the keel, and number 19-24 in 10 µm.

Original Description

Basionym: Bacillaria paradoxa
Author: Gmelin 1788
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Kociolek, P. (2011). Bacillaria paradoxa. In Diatoms of the United States. Retrieved June 19, 2013, from http://westerndiatoms.colorado.edu/taxa/species/bacillaria_paradoxa

Species: Bacillaria paradoxa

Contributor: Pat Kociolek

Reviewer: Sam Rushforth

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Image Credit: Pat Kociolek

  1. Valves linear to linear-lanceolate
  2. Keel placed along center of valve

Valves are isopolar, linear to linear-lanceolate, sometimes with slightly undulate margins, tapering to narrow apices. The keel is located in the center of the valve.

Compare

Placement of the keel in the center of the valve makes this species easy to distinguish from the other genera in this group. No other species of Bacillaria occur in the USA.

Citations

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Bacillaria paradoxa CAS

North American Diatom Ecological Database (NADED)

NADED ID: 76001

Autecology Discussion

Habits

Size Range

101-1000 µm3 (ie Amphora veneta)

Motility

moderately motile (e.g. Navicula tripunctata)

Attachment

other (e.g. tubes or thallose)

Habitat

benthic

Colony

colonies common

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

Bacillaria paradoxa

Distribution

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

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

Bacillaria paradoxa

Responses

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