Home / Chlorophyceae / Colonies /Non-flagellated / Pediastrum
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Name derivation:
“Flat star” Flat Pedi- star –astrum
Classification:
Pediastrum Meyen 1829; 15 of 405 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Sphaeropleales; Family Hydrodictyaceae
Morphology:
Nonmotile, multinucleated cells that can form a flat colony one cell thick. Individual cells form together with at least 4 cells up to 128 cells in concentric rings making a flat plate that resembles a snowflake. Cells can be cone like or polyhedral with protrusions. The cells are often notched or lobed, sometimes bearing short horns or bristles that can both improve its buoyancy in the water column and help to prevent predation. The cell walls may be smooth or ornamented. Asexual reproduction.
Similar genera:
Habitat:
These algae are found in lakes and ponds and along shores, where water is rich in nutrients, especially nitrogen; they are rare in deep water. Can produce taste/odor problems in drinking water.
References:
Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 28 September 2013. Meyen, F.J.F. 1829. Beobachtungen über einige niedere Algenformen. Nova Acta Physico-Medica Academiae Caesareae Leopoldino-Carolinae Naturae 14: 768-778, pl. XLIII.