Home / Greens /Colonies / Non-flagellated / Ankistrodesmus
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Name derivation:
“Bound fishhook – Fishhook Ankistro- bound –desmus
Classification:
Ankistrodesmus Corda 1838; 18 of 149 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Sphaeropleales; Family Selenastraceae Synonym in PhycoKey: Monoraphidium Komárková-Legnerová 1969, was separated because it doesn’t form colonies; Ankistrodesmus when growing rapidly also doesn’t form colonies.
Morphology:
Unicells or colonies of loosely bound unicells. Fiber-shaped cells are either straight, bent, or spiral. Needle like, sometimes curving. Unicellular but can be found in clusters or twining around one another. In PhycoKey the colonial form is deemed dominant over unicells, so the user is directed to the non-flagellate colonial greens even when selecting Ankistrodesmus from the non-flagellate unicellular greens.
Similar genera:
Raphidiopsis (cyanobacteria, Nostocaceae) is difficult to parse from unicellular Ankistrodesmus (Price 2017, personal communication). In fresh samples Ankistrodesmus has a brighter green color, but with such small cells color distortion occurs in microscopy. In samples preserved with Lugol’s Solution the color difference is not apparent. When preserved with formalin or formalin-sugar solution the pigments are bleached.
Habitat:
Freshwater ponds and lakes.
References:
Corda, J.-A.-C. 1838. Nouvelles observations microscopiques. Almanach de Carlsbad 8: 179-198. 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. Komárková-Legnerová, J. 1969. The systematics and ontogenesis of the genera Ankistrodesmus Corda and Monoraphidium gen. nov. In: Studies in Phycology. (Fott, B. Eds), pp. 75-144. Stuttgart: Schweizerbart'sche. Price, K. 2016. Microbiologist, Department of Environmental Protection. Bureau of Laboratories, 2575 Interstate Dr., Harrisburg, PA 17110