Pelvic claspers confirm chondrichthyan-like internal fertilization in arthrodires

@article{Ahlberg2009PelvicCC,
  title={Pelvic claspers confirm chondrichthyan-like internal fertilization in arthrodires},
  author={Per Erik Ahlberg and Kate Trinajstic and Zerina Johanson and John Long},
  journal={Nature},
  year={2009},
  volume={460},
  pages={888-889}
}
Recent finds demonstrate that internal fertilization and viviparity (live birth) were more widespread in the Placodermi, an extinct group of armoured fishes, than was previously realized. Placoderms represent the sister group of the crown group jawed vertebrates (Gnathostomata), making their mode(s) of reproduction potentially informative about primitive gnathostome conditions. An ossified pelvic fin basipterygium discovered in the arthrodire Incisoscutum ritchiei was hypothesized to be… 

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