Cocconeis fluviatilis

Wallace 1960      Category: Monoraphid
BASIONYM: Cocconeis fluviatilis Wallace 1960

Chamaepinnularia soehrensis

 

Cocconeis klamathensis

LM scalebar = 10 µm = 40 pixels.



Observations

Contributor: Marina Potapova - November 2010
Length Range: 20-24 µm
Width Range: 13-19 µm
Striae in 10 µm: 12-13

Description

Valves are elliptic. Raphe (R) valve has a narrow axial area and a vary small circular central area, or no distinct central area at all. Raphe is straight, filiform. Distal raphe ends are straight, expanded externally. Proximal raphe ends are externally straight, slightly expanded. Striae are radiate, interrupted by a hyaline rings positioned close to valve margin. Areolae are usually well distinguished under LM, 15-25 in 10 µm, and are arranged into longitudinal rows. Rapheless (RL) valve with linear to linear-lanceolate axial area and radiate striae. Areolae are much smaller in raphe than in rapheless valve, but in both valves areolae are smaller near the axial area and are getting conspicuously larger towards the valve margins.



Original Description

Basionym: Cocconeis fluviatilis
Author: Wallace 1960
Length Range: 23-24 µm
Width Range: 13-19 µm
Striae in 10 µm: 16 along raphe, 12 near margin

Original Description

The rapheless valve is somewhat similar to Cocconeis intermedia Herib. and Perag. It differs from this in that the puncta which make up the striae in this new species become progressively heavier and longer as they approach the valve margin, 16 striae in 10 μ in the middle (as measured along the raphe) and 12 striae in 10 μ at the margin. The raphe valve has the same striae count, but the striae are finely punctate throughout. An interruption, as found in Cocconeis placentula Ehr. and its varieties is present, but the lower striae number in this species removes it from the Cocconeis placentula complex.

Original Images

Original text and images reproduced with permission by Academy of Natural Sciences of Philadelphia.


Cite This Page:
Potapova, M. (2010). Cocconeis fluviatilis. In Diatoms of the United States. Retrieved October 25, 2014, from http://westerndiatoms.colorado.edu/taxa/species/cocconeis_fluviatilis

Species: Cocconeis fluviatilis

Contributor: Marina Potapova

Reviewer: Kalina Manoylov

Citations

Wallace, J. (1960). New and variable diatoms. Notulae Naturae 331: 1-8.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Cocconeis fluviatilis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 16010

Autecology Discussion

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

Cocconeis fluviatilis


EMAP Response Plots

Cocconeis fluviatilis


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.