Home / Diatoms / Pennate / Colonies / Fragilariopsis
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Name derivation:
Similar to Fragilaria.
Classification:
Fragilariopsis Hustedt in Schmidt 1913; 23 of 29 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Bacillariales; Family Bacillariaceae
Morphology:
Ribbon-shaped, straight and occasionally slightly curved colonies with no interspace between adjacent cells. Each cell contains two chloroplasts that are placed against the girdle. In girdle view, the cells are linear with a flattened valve face and a high pervalvar axis due to a high valve mantle and broad girdle bands. The raphe is located along the bend between valve face and mantle or slightly displaced towards the mantle and hence makes up a part of the mantle (Lundholm and Hasle 2010).
Similar genera:
Pseudo-Nitzschia (unicells). Separated from Fragilaria by the presence of a marginal raphe on both frustules.
Habitat:
Arctic marine ice and plankton, various species are often the most abundant diatoms.
Toxicity:
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 15 May 2013. Lundholm, N., and G.R. Hasle 2010. Fragilariopsis (Bacillariophyceae) of the Northern Hemisphere – morphology, taxonomy, phylogeny and distribution, with a description of F. pacifica sp. nov. Phycologia 49(5):438-460.