Home / Bacillariophyceae / Centric / Unicells / Actinocyclus
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Name derivation:
‘Cyclic ray’ (Gr.) – Actino- ray or beam; cyclus – cyclic
Classification:
Actinocyclus Ehrenberg, 1837. Of 388 species descriptions only 55 are currently accepted. Order Coscinodiscales; Family Hemidiscaceae
Morphology:
Unicells 16 – 48 µm diameter, barrel-shaped centric diatom with multiple discoid chloroplasts. One valve is concave, the other conves. Punctae on valve faces are arranged in ‘rays’ from the center to the rim.
Similar genera:
Habitat:
Aufwuchs (not firmly attached) on seaweeds and in nearshore marine plankton. Increasingly occurring in eutrophied freshwater lakes including bays of the Laurentian Great Lakes of Canada and USA.
References:
Ehrenberg, C.G. 1837. Nachricht des Hrn Agassiz in Neuchatel über den ebenfalls aus mikroskopichen Kiesel-Organismen gebildeten Polirschiefer von Oran in Afrika. 1837: 59-61. Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 10 September 2013.