Non-ammocoete larvae of Palaeozoic stem lampreys.

@article{Miyashita2021NonammocoeteLO,
  title={Non-ammocoete larvae of Palaeozoic stem lampreys.},
  author={Tetsuto Miyashita and Robert W. Gess and Kristen Tietjen and Michael I. Coates},
  journal={Nature},
  year={2021}
}
Ammocoetes-the filter-feeding larvae of modern lampreys-have long influenced hypotheses of vertebrate ancestry1-7. The life history of modern lampreys, which develop from a superficially amphioxus-like ammocoete to a specialized predatory adult, appears to recapitulate widely accepted scenarios of vertebrate origin. However, no direct evidence has validated the evolutionary antiquity of ammocoetes, and their status as models of primitive vertebrate anatomy is uncertain. Here we report larval… 

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