Glaucophyte

The glaucophytes are a small group of freshwater microscopic algae.[1] Together with the red algae (Rhodophyta) and green algae plus land plants (Viridiplantae or Chloroplastida), they form the Archaeplastida.

Glaucophyta
Glaucocystis sp.jpg
Glaucocystis sp.
Scientific classification e
Unrecognized taxon (fix): Glaucophyta
Class
  • Glaucocystophyceae Schaffner 1922
Synonyms
  • Glaucocystophyta Kies & Kremer, 1986

The glaucophytes are of interest because they may be similar to the original algal type that led to green plants and red algae.[1][2] The relationships between these groups are not yet clear,[3] and the glaucophytes in particular need more study.

Characteristics

The chloroplasts of glaucophytes are known as 'cyanelles'. Unlike the chloroplasts in other organisms, they have a peptidoglycan layer, like bacterial cell walls. This is thought to be a relic of the endosymbiotic origin of plastids from cyanobacteria.[1]

Glaucophytes have the photosynthetic pigment chlorophyll a.[1] They harvest light with the same type of pigment molecules as do cyanobacteria and red algae.[1] Green algae and land plants have lost that pigment, which is known as phycobiliprotein.[4]

Glaucophyte mitochondria and flagella (if present) are similar to forms found in some green algae.[4]

Classification

Only 13 species of glaucophytes are known, none of which is particularly common in nature.[1] There are three genera.

The glaucophytes were previously placed in the order Chlorococcales.[5]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Patrick J. Keeling (2004). "Diversity and evolutionary history of plastids and their hosts". American Journal of Botany. 91 (10): 1481–1493. doi:10.3732/ajb.91.10.1481. PMID 21652304. S2CID 17522125. Archived from the original on 2008-02-27. Retrieved 2014-07-03.
  2. Kim, Eunsoo & Graham, Linda E. (2008). "EEF2 analysis challenges the monophyly of Archaeplastida and Chromalveolata". PLOS ONE. 3 (7): e2621. Bibcode:2008PLoSO...3.2621K. doi:10.1371/journal.pone.0002621. PMC 2440802. PMID 18612431.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. Palme J.D; Soltis D.E. & Chase M.W. (2004). "The plant tree of life: an overview and some points of view". American Journal of Botany. 91 (10): 1437–1445. doi:10.3732/ajb.91.10.1437. PMID 21652302. Archived from the original on 2010-10-09. Retrieved 2014-07-03.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. 4.0 4.1 Skuja A. 1948. Taxonomie des Phytoplanktons einiger Seen in Uppland, Schweden. Symbolae Botanicae Upsalienses 9 (3): 1-399.
  5. Glaucocystis