Acoel flatworms: earliest extant bilaterian Metazoans, not members of Platyhelminthes.

  title={Acoel flatworms: earliest extant bilaterian Metazoans, not members of Platyhelminthes.},
  author={I{\~n}aki Ruiz-Trillo and Marta Riutort and D. Timothy J. Littlewood and Elisabeth Anne Herniou and Jaume Bagu{\~n}{\'a}},
  volume={283 5409},
Because of their simple organization the Acoela have been considered to be either primitive bilaterians or descendants of coelomates through secondary loss of derived features. Sequence data of 18S ribosomal DNA genes from non-fast evolving species of acoels and other metazoans reveal that this group does not belong to the Platyhelminthes but represents the extant members of the earliest divergent Bilateria, an interpretation that is supported by recent studies on the embryonic cleavage pattern… 

Acoel Flatworms Are Not Platyhelminthes: Evidence from

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    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2009
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Phylogenetic distribution of microRNAs supports the basal position of acoel flatworms and the polyphyly of Platyhelminthes

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  • J. BaguñáM. Riutort
  • Biology
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2004
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The Hox gene complement of acoel flatworms, a basal bilaterian clade

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Back in time: a new systematic proposal for the Bilateria

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  • S. Morris
  • Environmental Science
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 1998
A surprising new discovery of eggs with blastomeres and embryos with well-defined anatomy from the Cambrian of China and Siberia promises to extend the arena of debate on the nature of the earliest animals and when they originated.

Evidence that two types of 18S rDNA coexist in the genome of Dugesia (Schmidtea) mediterranea (Platyhelminthes, Turbellaria, Tricladida).

The 1st case of 18S rDNA polymorphism within a metazoan species is reported and the need for analyzing a large number of clones whenever 18S sequences obtained by PCR amplification and cloning are being used in phylogenetic reconstruction is stressed.

The interrelationships of all major groups of Platyhelminthes: phylogenetic evidence from morphology and molecules

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