World Library  
Flag as Inappropriate
Email this Article

Chromista

Article Id: WHEBN0000244980
Reproduction Date:

Title: Chromista  
Author: World Heritage Encyclopedia
Language: English
Subject: Thomas Cavalier-Smith, Kingdom (biology), Algae, Chlorophyll c, Eukaryotes
Collection: Eukaryotes, Protista
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Chromista

The Chromista are a eukaryotic supergroup, probably polyphyletic,[1][2] which may be treated as a separate kingdom or included among the Protista. They include all algae whose chloroplasts contain chlorophylls a and c, as well as various colorless forms that are closely related to them. These chloroplasts are surrounded by four membranes, and are believed to have been acquired from some red algae.

Contents

  • Groups 1
    • Chromophycées (Chadefaud, 1950) 1.1
    • Chromophyta (Christensen 1962, 1989) 1.2
    • Chromophyta (Bourrelly, 1968) 1.3
    • Chromista (Cavalier-Smith, 1981) 1.4
    • Chromalveolata (Adl et al., 2005) 1.5
    • Chromista (Cavalier-Smith, 2010) 1.6
  • History and controversy 2
  • See also 3
  • References 4
  • External links 5

Groups

Chromista has been defined in different ways at different times. The name Chromista was first introduced by Cavalier-Smith in 1981;[3] the earlier names Chromophyta, Chromobiota and Chromobionta correspond to roughly the same group.

It has been described as consisting of three different groups:[4]

In 2010, Thomas Cavalier-Smith indicated his desire to move Alveolata, Rhizaria and Heliozoa into Chromista.[5]

Some examples of classification of the Chromista and related groups are shown below.[6][7]

Chromophycées (Chadefaud, 1950)

The Chromophycées (Chadefaud, 1950),[8] renamed Chromophycota (Chadefaud, 1960),[9] included the current Ochrophyta (autotrophic Stramenopiles), Haptophyta (included in Chrysophyceae until Christensen, 1962), Cryptophyta, Dinophyta, Euglenophyceae and Choanoflagellida (included in Chrysophyceae until Hibberd, 1975).

Chromophyta (Christensen 1962, 1989)

The Chromophyta (Christensen 1962, 1989), defined as algae with chlorophyll c, included the current Ochrophyta (autotrophic Stramenopiles), Haptophyta, Cryptophyta, Dinophyta and Choanoflagellida. The Euglenophyceae were transferred to the Chlorophyta.

Chromophyta (Bourrelly, 1968)

The Chromophyta (Bourrelly, 1968) included the current Ochrophyta (autotrophic Stramenopiles), Haptophyta and Choanoflagellida. The Cryptophyceae and the Dinophyceae were part of Pyrrhophyta (= Dinophyta).

Chromista (Cavalier-Smith, 1981)

The Chromista (Cavalier-Smith, 1981) included the current Stramenopiles, Haptophyta and Cryptophyta.

Chromalveolata (Adl et al., 2005)

The Chromalveolata (Cavalier-Smith, 1981) included Stramenopiles, Haptophyta, Cryptophyta and Alveolata.

Chromista (Cavalier-Smith, 2010)

The Chromista (Cavalier-Smith, 2010) included Harosa (Stramenopiles, Alveolata and Rhizaria) and Hacrobia (Haptophyta, Cryptophyta and centrohelid Heliozoa).

History and controversy

Molecular trees have had some difficulty resolving relationships between the different groups. All three may share a common ancestor with the alveolates (see chromalveolates), but there is evidence that suggests that the haptophytes and cryptomonads do not belong together with the heterokonts.[1][10]

See also

References

  1. ^ a b Laura Wegener Parfrey, Erika Barbero, Elyse Lasser, Micah Dunthorn, Debashish Bhattacharya, David J Patterson, and Laura A Katz (December 2006). "Evaluating Support for the Current Classification of Eukaryotic Diversity". PLoS Genet. 2 (12): e220.  
  2. ^ Cavalier-Smith T, Allsopp MT, Chao EE (November 1994). "Chimeric conundra: are nucleomorphs and chromists monophyletic or polyphyletic?". Proc. Natl. Acad. Sci. U.S.A. 91 (24): 11368–72.  
  3. ^ T. Cavalier-Smith (1981). "Eukaryote kingdoms: seven or nine?". Biosystems 14 (3–4): 461–481.  
  4. ^ Csurös M, Rogozin IB, Koonin EV (May 2008). "Extremely intron-rich genes in the alveolate ancestors inferred with a flexible maximum-likelihood approach". Mol. Biol. Evol. 25 (5): 903–11.  
  5. ^ Cavalier-Smith T (June 2010). "Kingdoms Protozoa and Chromista and the eozoan root of the eukaryotic tree". Biol. Lett. 6 (3): 342–5.  
  6. ^ Reviers, B. de. (2006). Biologia e Filogenia das Algas. Editora Artmed, Porto Alegre, pp. 156-157.
  7. ^ W. H. Blackwell (2009). Chromista revisited: A dilemma of overlapping putative kingdoms, and the attempted application of the botanical code of nomenclature. Phytologia 91(2).
  8. ^ Chadefaud, M. 1950. Les cellules nageuses des Algues dans l'embranchement des Chromophycées. Comptes rendus hebdomadaire de l'Académie des Sciences, Paris 231: 788–790.
  9. ^ Chadefaud, M. 1960. Les végétaux non vasculaires (Cryptogamie). In Chadefaud, M., and Emberger, L. Traité de Botanique Systématique. Tome I. Paris.
  10. ^ Burki F, Shalchian-Tabrizi K, Minge M; et al. (2007). Butler, Geraldine, ed. "Phylogenomics Reshuffles the Eukaryotic Supergroups". PLoS ONE 2 (8): e790.  

External links

  • UCMP: Introduction to the Chromista
  • Encyclopedia of Life: Chromista
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.