Navicula subminuscula

Manguin 1942      Category: Symmetrical biraphid
BASIONYM: Navicula subminuscula Manguin 1942
SYNONYM(S): Eolimna subminuscula (Manguin) Moser, Lange-Bertalot and Metzeltin 
GENUS CONSIDERED: Eolimna

Navicula subconcentrica

 

Navicula subrhynchocephala
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LM scalebar = 10 µm = 80 pixels.

Observations

Contributor: Marina Potapova - May 2009
Length Range: 7.3-10.5 µm
Width Range: 3.3-5.0 µm
Striae in 10 µm: 20-28

Description

Valves are elliptical-lanceolate, with acute ends, 3.3-5.0 µm wide, 7.3-10.5 µm long. The raphe is filiform, with slightly bent branches. The axial area is thickened, linear, only slightly widened in the center. Striae are radiate throughout, 20-28 in 10 µm, uniseriate. Areolae round or transapically elongated, often visible in LM .

Original Description

Basionym: Navicula subminuscula
Author: Manguin 1942
Length Range: 9–10 µm
Width Range: 4.5 µm
Striae in 10 µm: 25

Original Description

Valve eliptique lancéolée, à extrémités arrondie aiguës. Raphé droit; area axial très étroit, non élargi autour du nodule central. Stries radiales, un peu plus distantes dans la partie valvaire médiane, environ 25 en 10 µm, vers les extremites plus de 30. Long. 9-10 µm, larg. 4.5 µm. Pl. II, fig. 39. Cette espèce ne diffère de N. Lenzi Krasske (11: p. 556, Pl. XIX, fig. 11, 12) que par ses stries non ponctuées. Santa-Maria (XIV) R.: cuvette rocheuse à Potamogeton fluitans

Original Images

Original text and images reproduced with permission by Paris: Le Laboratoire de cryptogamie du Museum national d'histoire naturelle.

Cite This Page:
Potapova, M. (2009). Navicula subminuscula. In Diatoms of the United States. Retrieved May 25, 2013, from http://westerndiatoms.colorado.edu/taxa/species/Navicula_subminuscula

Species: Navicula subminuscula

Contributor: Marina Potapova

Reviewer: Sam Rushforth

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Image Credit: Marina Potapova

  1. Valves elliptic-lanceolate
  2. Axial area narrow, thickened
  3. Central area absent
  4. Striae punctate

Valves elliptic-lanceolate and relatively small in size. The axial area is thickened, and may appear raised above the valve face. Valves lack a distinct central area. Striae are punctate and areolae may be visible in LM.

Compare

Navicula subminuscula is shorter with more radiate striae and a thicker axial area than Craticula molestiformis. Navicula subminuscula can be confused with Karayaevia suchlandtii because of the thinkened axial area on the raphe valve. The latter, however, can be distinguished by rounded ends and presence of the rapheless valve. Mayamaea agrestis has narrower valves and shortened striae in the middle portion of the valve separating it from N. subminuscula.

Karayevia suchlandtii

Craticula molestiformis

(Hustedt) Mayama

Mayamaea agrestis

(Hustedt) Lange-Bertalot

Citations

Lange-Bertalot, H. and Rumrich, U. (1981). The taxonomic identity of some ecologically important small Naviculae. R. Ross (ed.), Proceedings of the Sixth Symposium on Recent and Fossil Diatoms, Budapest, September 1-5, 1980, Taxonomy-Morphology-Ecology-Biology. Koeltz Publishing, Koenigstein. pp. 135-154.

Manguin, E. (1942). Contribution à la connaissance des Diatomées d'eau douce des Açores. Travaux Algologiques, Sér. 1. Muséum National d'Histoire Naturelle, Laboratoire de Cryptogamie, Vol: 2, 115-160, 4 pls.

Moser, G., Lange-Bertalot, H. and Metzeltin, D. (1998). Insel der Endemiten Geobotanisches Phänomen Neukaledonien (Island of endemics New Caledonia - a geobotanical phenomenon). Bibliotheca Diatomologica 38:464 pp.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Navicula subminuscula CAS

North American Diatom Ecological Database (NADED)

NADED ID: 46562

Autecology Discussion

Eutraphentic species

Habits

Size Range

11-100 µm3 (ie Achnanthidium)

Motility

moderately motile (e.g. Navicula tripunctata)

Attachment

unattached

Habitat

benthic

Colony

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

Navicula subminuscula

Distribution

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

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

Navicula subminuscula

Responses

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