A Possible Lower Cambrian Chaetognath (Arrow Worm)

@article{Chen2002APL,
  title={A Possible Lower Cambrian Chaetognath (Arrow Worm)},
  author={Jun‐yuan Chen and Diying Huang},
  journal={Science},
  year={2002},
  volume={298},
  pages={187 - 187}
}
The phylum Chaetognatha (also called arrow worm), with only about 100 living species, is found in oceans throughout the world and plays an important role in the food web as primary predators ([1][1]). Its fossil record, however, is sparse. The Carboniferous Paucijaculum samamithion has been the only definitive fossil chaetognath ([2][2]). Some of the Cambrian protoconodonts could be grasping spines of this group ([3][3]). The Middle Cambrian Amiskwia was considered as a chaetognath ([4][4… 

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