Stauroneis phoenicenteron

(Nitzsch) Ehrenberg 1843      Category: Symmetrical biraphid
BASIONYM: Bacillaria phoenicenteron Nitzsch 1817

Stauroneis pax

 

Stauroneis pikuni
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LM scalebar = 10 µm = 20 pixels.

Observations

Contributor: Loren Bahls - November 2011
Length Range: 129-199 µm
Width Range: 26-35 µm
Striae in 10 µm: 15-18

Description

Valves are lanceolate with broadly rounded, non-protracted apices. The axial area is narrow, widening slightly near the central area. The stauros is rectangular, narrowing slightly toward the valve margins. Shortened striae may be present in the central area. The raphe is lateral with straight and somewhat inflated proximal ends. Striae are radiate throughout. Areolae number 13-17 in 10 µm.

Note that Patrick and Reimer (1966, plate 29, fig. 2) mistakenly illustrate the species Stauroneis baileyi, instead of S. phoenicenteron, in their volume.

Original Description

Basionym: Bacillaria phoenicenteron
Author: Nitzsch 1817
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Bahls, L. (2011). Stauroneis phoenicenteron. In Diatoms of the United States. Retrieved May 18, 2013, from http://westerndiatoms.colorado.edu/taxa/species/stauroneis_phoenicenteron

Species: Stauroneis phoenicenteron

Contributor: Loren Bahls

Reviewer: Mark Edlund

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Image Credit: Loren Bahls

  1. Valves lanceolate and large, up to 35 microns wide
  2. Apices rounded
  3. Proximal raphe ends straight
  4. Striae 15-18 in 10 µm

Stauroneis phoenicenteron has large lanceolate valves with rounded ends. Proximal raphe ends are straight. Striae are moderately coarse, but no fewer than 15 in 10 µm.

Compare

Stauroneis phoenicenteron has smaller and narrower valves and more closely spaced striae than S. baileyi and S. rex. Stauroneis gracilis has curved, rather than straight proximal raphe ends.

Stauroneis rex

Stauroneis gracilis

Stauroneis baileyi

Ehrenberg

Citations

Bahls, L. (2010). Stauroneis in the Northern Rockies: 50 species of Stauroneis sensu stricto from western Montana, northern Idaho, northeastern Washington and southwestern Alberta, including 16 species described as new. Northwest Diatoms, Volume 4. The Montana Diatom Collection, Helena, 172 pp.

Ehrenberg, C.G. (1843). Verbreitung und Einfluß des mikroskopischen Lebens in Süd- und Nord-Amerika. Abhandlungen der Königlichen Akademie der Wissenschaften zu Berlin, 1841: 291-445, 4 Tafel.

Lange-Bertalot, H., Cavacini, P., Tagliaventi, N. and Alfinito, S. (2003). Diatoms of Sardinia: Rare and 76 new species in rock pools and other ephemeral waters. Iconographia Diatomologica 12, 438 pp.

Reichardt, E. (1995). Die Diatomeen (Bacillariophyceae) in Ehrenbergs Material von Cayenne, Guyana Gallica (1843). Volume 1, Iconographia Diatomologica (H. Lange-Bertalot, ed.). Koeltz Scientific Books, Konigstein.

Van de Vijver, B., Beyens, L. and Lange-Bertalot, H. (2004). The genus Stauroneis in Arctic and Antarctic Regions. Bibliotheca Diatomologica 50, 312 pp.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Stauroneis phoenicenteron CAS

North American Diatom Ecological Database (NADED)

NADED ID: 62015

Autecology Discussion

In the Northern Rockies Stauroneis phoenicenteron is widely distributed in the benthos of lakes and ponds with circumneutral pH (mean pH = 7.1) and low specific conductance (mean SC = 34 µS/cm).

Images

Skinner Pond #2, Beaverhead County, Montana: Home of Stauroneis phoenicenteron.

Credit/Source: Loren Bahls

Habits

Size Range

10,001-100,000 µm3 (ie Cymbella tumida)

Motility

moderately motile (e.g. Navicula tripunctata)

Attachment

unattached

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

Stauroneis phoenicenteron

Distribution

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

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

Stauroneis phoenicenteron

Responses

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