, Volume 305, Issue 1–3, pp 37–43 | Cite as

5S rRNA sequences of 12 species of flatworms: implications for the phylogeny of the Platyhelminthes

  • B. I. Joffe
  • K. M. Valiejo Roman
  • V. Ya. Birstein
  • A. V. Troitsky
Taxonomy and phylogeny


5S rRNAs from 12 species of free living and parasitic platyhelminthes were sequenced. In the phylogenetic analysis, attention was focused on the statistical estimates of the trees corresponding to existing phylogenetic hypotheses. The available 5S rRNA data agree well with widely accepted views on the relationships between the Acoela, Polycladida, Tricladida, and Neorhabdocoela; our analysis of the published 18S rRNA sequences also demonstrated good correspondence between these views and molecular data. With available 5S rRNA data the hypothesis that the dalyellioid turbellarians is the sister group of the Neodermata is less convincing than the hypotheses proposing the Neodermata as the sister group of the Neorhabdocoela, or of the Seriata, or of the branch uniting them. A relatively low rate of base replacement in parasitic flatworms, probably, accounts for the uncertain position of the Neodermata, while a relatively high rate in planarians may explain a relatively too early divergence of the Tricladida in several published phylogenetic trees constructed from various rRNA data.

Key words

5S rRNA Platyhelminthes Turbellaria parasitic flatworms phylogeny 


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  1. Baverstock, P. R., R. Fielke, A. M. Johnson, R. A. Bray & I. Beveridge, 1991. Conflicting phylogenetic hypothesis for the parasitic platyhelminths tested by partial sequencing of 18S ribosomal RNA. Int. J. Parasitol. 21: 329–339.Google Scholar
  2. Brooks, D. R., 1989. The phylogeny of the Cercomeria (Platyhelminthes: Rhabdocoela) and general evolutionary principles. J. Parasitol. 75: 606–616.Google Scholar
  3. Ehlers, U., 1985. Das phylogenetishe System der Plathelminthes. G. Fisher, Stuttgart-New York, 317 pp.Google Scholar
  4. Felsenstein, J., 1990. PHYLIP 3.3. University of Herbarium, Berkley, California.Google Scholar
  5. Hendriks, L., E. Huysmans, A. Van den Berghe & R. De Wachter, 1986. Primary structure of 5he 5S ribosomal RNAs of 11 arthropods and applicability of 5S RNA to the study of metazoan evolution. J. Mol. Evol. 24: 103–109.Google Scholar
  6. Hori, H., A. Muto, S. Osawa, M. Takai, K.-Y. Lue & M. Kawakatsu, 1988. Evolution of turbellaria as deduced from 5S ribosomal RNA sequences. Fortschritte Zool./Progress Zool. 36: 163–167.Google Scholar
  7. Hori, H. & S. Osawa, 1987. Origins and evolution of organisms as deduced from 5S rRNA sequences. Mol. Biol. Evol. 4: 445–472.Google Scholar
  8. Joffe, B. I., G. S. Slusarav & T. A. Timofeeva, 1987. Stroenie glotki mongenei i ih phylogeneticheskie sviasi s turbellariyami. [Pharynx structure in the monogeneans and their phylogenetic relationships with the turbellarians.] Parasitologia (St-Petersburg) 21: 472–481.Google Scholar
  9. Joffe, B. I. & G. K. Chubrik, 1988. Stroenie glotki trematod i phylogeneticheskie sviasi mezhdu Trematoda i Turbellaria. [The structure of the pharynx in trematodes and phylogenetic relations between Trematoda and Turbellaria]. Parasitologia (St-Petersburg) 22: 297–303.Google Scholar
  10. Kotikova, E. A. & B. I. Joffe, 1988. On the nervous system of the dalyellioid turbellarians. Fortschiritte Zool. /Progress Zool. 36: 191–194.Google Scholar
  11. Lake, A. J., 1989. Origin of the eukaryotic nucleus determined by rate-invariant analyses of ribosomal RNA genes. In B. Fernholm, K. Bremer & H. Jornvall (eds), The hierarchy of life. Elsevier Science Publishers, Amsterdam: 87–101.Google Scholar
  12. Ohama, T., T. Kumazaki, H. Hori, S. Osawa & M. Takai, 1983. Fresh water planarians and a marine planaria are relatively dissimilar in the 5S rRNA sequences. Nucleic Acids Res. 11: 433–436.Google Scholar
  13. Rieger, R. M., S. Tyler, J. P. S. Smith & G. E. Rieger, 1990. Platyhelminthes: Turbellaria. In F. W. Harrison & B. J. Bogitsh (eds), Platyhelminthes and Rhynchocoela, vol. 3 in F. W. Harrison (ed.) Microscopic anatomy of invertebrates. Wiley-Liss, New York: 7–140.Google Scholar
  14. Rohde, K., 1990. Phylogeny of the Platyhelminthes, with special reference to parasitic groups. Int. J. Parasitol. 20: 979–1007.Google Scholar
  15. Ruitort, M., K. G. Field, J. M. Turbeville, R. A. Raff & J. Baguñá, 1992a Enzyme electrophoresis, 18S rRNA sequences, and levels of phylogenetic resolution among several species of freshwater planarians (Platyhelminthes, Tricladida, Paludicola). Can. J. Zool. 70: 1425–1439.Google Scholar
  16. Ruitort, M., K. G. Field, R. A. Raff & J. Baguñá, 1992b. 18S rRNA sequences and phylogeny of Platyhelminthes. Biochem. Syst. Ecol. 21: 71–77.Google Scholar
  17. Specht, T., J. Wolters & V. A. Erdmann, 1990. Compilation of 5S rRNA and 5S rRNA gene sequences. Nucl. Acids Res. 18: 2215–2230.Google Scholar
  18. Troitsky, A. V., Yu E. Melekhovets, G. M. Rakhimova, V. K. Bobrova, K. M. Valiejo-Roman & A. S. Antonov, 1991. Angiosperm origin and early stages of seed plant evolution deduced from rRNA sequence comparisons. J. Mol. Evol. 32: 253–261.Google Scholar
  19. Wainwright, P., G. Hinkle, M. L. Sogin & S. K. Stickel, 1993. Monophyletic origins of the Metazoa: an evolutionary link with Fungi. Science 260: 340–342.Google Scholar

Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • B. I. Joffe
    • 1
  • K. M. Valiejo Roman
    • 2
  • V. Ya. Birstein
    • 3
  • A. V. Troitsky
    • 2
  1. 1.Zoological Institute RANSt-PetersburgRussia
  2. 2.A. N. Belozersky Institute of Physico-Chemical BiologyMoscow State UniversityMoscowRussia
  3. 3.N. K. Koltzov Institute of Developmental Biology RANMoscowRussia

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