Planothidium calcar
Edlund in Edlund, Soninkhishig, Williams and Stoermer 2001 Category: Monoraphid
BASIONYM: Achnanthes calcar Cleve 1891
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Marina Potapova - November 2011
Length Range: 9.7-21.2 µm
Width Range: 7.1-10.4 µm
Striae in 10 µm: 26-32
Description
Valves are elliptical, sometimes slightly constricted in the center. The axial area is narrow and linear on the raphe valve; the axial area is narrow and rhomboid on the rapheless valve. The central area on both valves is asymmetric, expanded to valve margins and contains a hood. The raphe is straight with sigmoid terminal fissures. The striae are fine, uniseriate and radiate throughout both valves.
Original Description
Basionym: Achnanthes calcar
Author: Cleve 1891
Length Range: 12 µm
Width Range: 9 µm
Striae in 10 µm: 24
Original Description
A. Calcar Cl. - Upper valve broadly elliptic, 0,012 m. m. in length and 0,009 m. m. in breadth, with about 24 striae in 0,01 m. m. It carries on the one side a horseshoe-like thickening, which is prolonged on the other half of the valve into a spur-like projection. The lower valve is not known with certainty, but in the same gathering, in which this species has been found, occurs a valve of similar outline and size, the striæ of which reach the raphe and are 25 in 0,01 m. m. That valve, which has a greta resemblance to Diadesmis lucidula Grun. (V. H. XIV, 40) may possibly be the lower valve of A. Calcar. Pl. III, fig. 8, (9 ?). Ab. 45, 47.
Original Images
Cite This Page:
Potapova, M. (2011). Planothidium calcar. In Diatoms of the United States. Retrieved May 18, 2013, from http://westerndiatoms.colorado.edu/taxa/species/planothidium_calcar
Species: Planothidium calcar
Contributor: Marina Potapova
Reviewer: Sarah Spaulding
Image Credit: Marina Potapova
- Valves elliptical
- Central area asymmetric
- Hood present on both valves
- Central area reaches valve margins
Valves are elliptical. The axial area is narrow and linear on the raphe valve; the axial area is narrow and rhomboid on the rapheless valve. The central area on both valves is asymmetric, expanded to the valve margins and contains a hood. The striae are fine and radiate throughout both valves.
Compare
Planothidium calcar, with its asymmetric central area and hood, is a distinctive species.
Citations
Cleve, P.T. (1891). The Diatoms of Finland. Actas Societas Pro Fauna et Flora Fennica 8 (2): 1-68.
Edlund, M.B., Soninkhishsig, N., Williams, R.M. and Stoermer, E.F. (2001). Biodiversity of Mongolia: Checklist of diatoms, including new distributional reports of 31 taxa. Nova Hedwigia 72(1-2):59-90.
Round, F. E. and Bukhtiyarova, L. (1996). Four new genera based on Achnanthes (Achnanthidium) together with a re-definition of Achnanthidium. Diatom Research 11: 345-361.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 155033
Autecology Discussion
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
Planothidium calcar
Distribution
The distribution map represents the relative abundance of this Planothidium calcar 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 Planothidium calcar was not recorded, or with a red circle indicating the relative abundance of Planothidium calcar.
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
Planothidium calcar
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.