A molecular phylogenetic framework for the phylum Ctenophora using 18S rRNA genes.

  title={A molecular phylogenetic framework for the phylum Ctenophora using 18S rRNA genes.},
  author={Mercha Podar and Steven H. D. Haddock and Mitchell L. Sogin and Gr. Harbison},
  journal={Molecular phylogenetics and evolution},
  volume={21 2},
This paper presents the first molecular phylogenetic analysis of the phylum Ctenophora, by use of 18S ribosomal RNA sequences from most of the major taxa. The ctenophores form a distinct monophyletic group that, based on this gene phylogeny, is most closely related to the cnidarians. Our results suggest that the ancestral ctenophore was tentaculate and cydippid-like and that the presently recognized order Cydippida forms a polyphyletic group. The other ctenophore orders that we studied (Lobata… 

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