Phalansterium is a genus of single-celled flagellated organisms comprising several species, which form colonies.[1] Phalansterium produces tetraspores.[2]

Phalansterium is hard to classify; it has a distinctive ultrastructure of its pericentriolar material. Molecular evidence places it in the Amoebozoa.[3][4]

It has been suggested that it is similar to the ancestral eukaryote.[5]


  1. ^ "Phalansterium". Encyclopedia of Life. 
  2. ^ Guiry, M.D.; Guiry, G.M. (2008). "Phalansterium". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved 2009-02-21. 
  3. ^ Thomas Cavalier-Smith, Ema E. -Y. Chaoa and Brian Oates (18 May 2004). "Molecular phylogeny of Amoebozoa and the evolutionary significance of the unikont Phalansterium". European Journal of Protistology. 40 (1): 21–48. doi:10.1016/j.ejop.2003.10.001. 
  4. ^ Nikolaev, Si; Berney, C; Petrov, Nb; Mylnikov, Ap; Fahrni, Jf; Pawlowski, J (Jun 2006). "Phylogenetic position of Multicilia marina and the evolution of Amoebozoa" (Free full text). International Journal of Systematic and Evolutionary Microbiology. 56 (Pt 6): 1449–58. doi:10.1099/ijs.0.63763-0. PMID 16738126. 
  5. ^ Cavalier-Smith T (March 2002). "The phagotrophic origin of eukaryotes and phylogenetic classification of Protozoa". Int. J. Syst. Evol. Microbiol. 52 (Pt 2): 297–354. doi:10.1099/00207713-52-2-297. PMID 11931142.