A new metazoan from the Vendian of the White Sea, Russia, with possible affinities to the ascidians

  title={A new metazoan from the Vendian of the White Sea, Russia, with possible affinities to the ascidians},
  author={Mikhail A. Fedonkin and Pat Vickers-Rich and Billie J. Swalla and Peter W. Trusler and Michael Hall},
  journal={Paleontological Journal},
Two specimens recovered from late Neoproterozoic shallow marine sediments of northern Russia may be the oldest known ascidians. Dated at around 555 Ma, these, together with the younger Ausia from the Nama Group in southwestern Africa, are probably relatives of these invertebrate chordates, which have a deep time origin predicted by molecular studies. 
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    Proceedings of the National Academy of Sciences of the United States of America
  • 1994
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