Home / Rhodophyceae / Microreds / Porphyridium
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Name derivation:
Porphyridium= Gr. Porphyra: purple dye + idion: similar to purpureum= L. purpureus: in purple, dull red with a slight dash of blue
Classification:
Porphyridium Nägeli 1849; 3 of 7 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Porphyridiales; Family Porphyridiaceae
Morphology:
Spherical to ovoid single cells, 5 – 16 um diameter, with one large stellate plastid, a prominent central pyrenoid, and solitary or often in irregular colonies with ill-defined mucilaginous matrix. Cells have with other organelles restricted to a small part of the cytoplasm around the plastid. Cells divide by a cleavage furrow that traverses the plastid. Colonies form a gelatinous coating on surfaces in freshwater brackish and marine environments and moist soils. Species are distinguished by plastid color.
Similar genera:
Habitat:
Coccoid cells occur in the extreme spray-mist upper intertidal zone at very exposed open coastal sites in the Northwest Atlatic (4.3-9.2 m above MLW; Johnson and Skutch, 1928c). Salt tolerant, freshwater and terrestrial cells also occur in salt marshes and soils of sea cliffs (cf. Sheath and Sherwood, 2002). Cells require 35 ppt (parts per thousand) salinity to actively compete with other algae, and are not inhibited by up to 45 ppt (Golueke and Oswald 1962).
References:
Golueke, C.G., and W.J. Oswald 1962. The mass culture of Porphyridium cruentum. Appl. Microbiol. 10:102-107. Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 19 September 2013. Johnson, D. S. and A. F. Skutch. 1928. Littoral vegetation on a headland of Mount Desert Island, Maine. Ecology 9: 118-215, 307-338. Nägeli, C. 1849. Gattungen einzelliger Algen, physiologisch und systematisch bearbeitet. Neue Denkschriften der Allg. Schweizerischen Gesellschaft für die Gesammten Naturwissenschaften 10(7): i-viii, 1-139, pls I-VIII. Sheath, R.G. & Sherwood, A.R. (2002). Phylum Rhodophyta (Red Algae). In: The freshwater algal flora of the British Isles. An identification guide to freshwater and terrestrial algae. (John, D.M., Whitton, B.A. & Brook, A.J. Eds), pp. 123-143. Cambridge: Cambridge University Press.