Articulated Palaeozoic fossil with 17 plates greatly expands disparity of early chitons

@article{Vendrasco2004ArticulatedPF,
  title={Articulated Palaeozoic fossil with 17 plates greatly expands disparity of early chitons},
  author={Michael J. Vendrasco and Troy E. Wood and Bruce Runnegar},
  journal={Nature},
  year={2004},
  volume={429},
  pages={288-291}
}
Modern chitons (Mollusca: Polyplacophora) possess a highly conserved skeleton of eight shell plates (valves) surrounded by spicules or scales, and fossil evidence suggests that the chiton skeleton has changed little since the first appearance of the class in the Late Cambrian period (about 500 million years before present, Myr bp). However, the Palaeozoic problematic taxon Multiplacophora, in spite of having a more complex skeleton, shares several derived characters with chitons. The enigmatic… Expand

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