Planothidium apiculatum
Planothidium apiculatum (Patrick) Lange-Bertalot 1999 Category: Monoraphid
BASIONYM: Achnanthes lanceolata var. apiculata Patrick 1945
LM scalebar = 10 µm = 40 pixels.
Observations
Contributor: Marina Potapova - December 2010
Length Range: 25-31 µm
Width Range: 9.0-12.7 µm
Striae in 10 µm: 10-12
Description
Valves are elliptical-lanceolate with apiculate apices. The raphe valve has a large rhomboid or transversely elliptical central area. The rapheless valve has an asymmetrical central area, expanded on one side to the valve margin. This asymmetrical central area also contains a hood on the internal valve surface. The raphe is straight with expanded external proximal endings. The striae are strongly radiate on the raphe valve and slightly radiate on the rapheless valve. The striae are multiseriate.
Original Description
Basionym: Achnanthes lanceolata var. apiculata
Author: Patrick 1945
Length Range: 28 µm
Width Range: 10-11 µm
Striae in 10 µm: 10-12
Original Description
Valvae elliptico-lanceolatae, 28 μ longae, 10-11 μ latae, apicibus apiculatis. Valva superior ad instar soleae equinae effigiem in medio ostendens, pseudoraphe anguste lanceolata; striis radiantibus, 10-12 in 10 μ. Valva inferior aream axialem angustam et aream centralem rotundatam exhibens; striis validis radiantibus, 10 in 10 μ.
Original Images
Cite This Page:
Potapova, M. (2010). Planothidium apiculatum. In Diatoms of the United States. Retrieved May 24, 2013, from http://westerndiatoms.colorado.edu/taxa/species/planothidium_apiculatum
Species: Planothidium apiculatum
Contributor: Marina Potapova
Reviewer: Rex Lowe
Image Credit: Marina Potapova
- Valves elliptical-lanceolate with apiculate apices
- Valves 9.0-12.7 μm wide
- Rapheless valve with a hood
Valves are elliptical-lanceolate with apiculate apices. The raphe valve has a large rhomboid or transversely elliptical central area. The rapheless valve has an asymmetrical central area, expanded at one side to the valve margin and containing a prominent hood . The striae are strongly radiate on the raphe valve and slightly radiate on the rapheless valve.
Compare
Planothidium apiculatum differs from other Planothidium species with a hood, such as P. frequentissimum, P. biporomum and P. rostratum, by large elliptical-lanceolate valves with apiculate apices. The raphe valves of small specimens may be difficult to differentiate from those of P. delicatulum. The rapheless valves of P. apiculatum, however, possess a hood – a feature not found in P. delicatulum.
Planothidium frequentissimum
Planothidium delicatulum
Planothidium rostratum
Planothidium biporomum
Citations
Lange-Bertalot, H. (1999). Neue Kombinationen von taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276-289.
Patrick, R.M. (1945). A taxonomic and ecological study of some diatoms from the Pocono Plateau and adjacent regions. Farlowia 2(2):143-221.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 155019
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 apiculatum
Distribution
The distribution map represents the relative abundance of this Planothidium apiculatum 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 apiculatum was not recorded, or with a red circle indicating the relative abundance of Planothidium apiculatum.
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 apiculatum
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.