Home / Greens /Colonies / Non-flagellated / Prototheca
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Name derivation:
Classification:
Prototheca W. Krüger in Zopf, 1894; 13 of 21 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Chlorellales; Family Chlorellaceae
Morphology:
Rosette colonies or unicells; colorless. Cells round to ellipsoid, 5- 40 µm diameter. Parasitic or saprophytic. Store starch. No flagellated stages nor sexual reproduction has been reported (Guiry and Guiry 2013).
Similar genera:
Chlorella. Prototheca is considered likely to be a colorless mutant.
Habitat:
Widespread in temperate and tropical freshwater, sewage, soil, and marine habitats. Colonize mammals, especially humans, cattle and dogs, internally and externally. When immune systems are compromised, can cause ‘protothecosis’ characterized by proliferation in the intestine, and eventually in the skin (cutaneous), kidneys, eyes and brain. Symptoms include subcutaneous discoloration and rash, papules and pustules. Also diarrhea, weight loss, weakness, eye inflammation, retinal detachment, ataxis and seizures. Possibly the only infectious green protist. .
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 07 May 2013. Krüger, W. 1894. Kurze Charakteristik einiger niedrerer Organismen im Saftfluss der Laubbäume. Hedwigia 33: 241-266.