Understanding form and function of the stem in early flattened echinoderms (pleurocystitids) using a microstructural approach

@article{Gorzelak2016UnderstandingFA,
  title={Understanding form and function of the stem in early flattened echinoderms (pleurocystitids) using a microstructural approach},
  author={Przemysław Gorzelak and Samuel Zamora},
  journal={PeerJ},
  year={2016},
  volume={4}
}
Pleurocystitid rhombiferans are among the most unusual echinoderms whose mode of life has been long debated. These echinoderms are usually interpreted as vagile epibenthic echinoderms, moving over the sea bottom by means of a flexible stem. Although their life habits and posture are reasonably well understood, the mechanisms that control the movement of stem are highly controversial. Specifically, it is unknown whether the stem flexibility was under the control of muscles or ligamentary mutable… 
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