Fossils from South China redefine the ancestral euarthropod body plan

@article{Aria2020FossilsFS,
  title={Fossils from South China redefine the ancestral euarthropod body plan},
  author={C{\'e}dric Aria and Fangchen Zhao and Han Zeng and Jin Guo and Maoyan Zhu},
  journal={BMC Evolutionary Biology},
  year={2020},
  volume={20}
}
BackgroundEarly Cambrian Lagerstätten from China have greatly enriched our perspective on the early evolution of animals, particularly arthropods. However, recent studies have shown that many of these early fossil arthropods were more derived than previously thought, casting uncertainty on the ancestral euarthropod body plan. In addition, evidence from fossilized neural tissues conflicts with external morphology, in particular regarding the homology of the frontalmost appendage.ResultsHere we… 

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The origin and evolution of the euarthropod labrum.

  • G. Budd
  • Biology, Environmental Science
    Arthropod structure & development
  • 2021

A new euarthropod with ‘great appendage’-like frontal head limbs from the Chengjiang Lagerstätte, Southwest China

Although, due to the absence of critical soft anatomy, the authors cannot elucidate the exact segmental affinities of these raptorial appendages, the possession of ‘great appendage’-like frontal head limbs is important for assessing the range of limb morphology evolved by early euarthropods.

Exceptional multifunctionality in the feeding apparatus of a mid-Cambrian radiodont

Stanleycaris and similar hurdiids provide an extreme example of the evolution of division of labor within the appendage of a stem euarthropod and suggest that this innovation may have facilitated the functional transition, from raptorial to sweep feeding, at the origin of the hurdiid clade.

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