The evolution of biramous appendages revealed by a carapace-bearing Cambrian arthropod

  title={The evolution of biramous appendages revealed by a carapace-bearing Cambrian arthropod},
  author={Dongjing Fu and David A. Legg and Allison C. Daley and Graham E. Budd and Yu Wu and Xingliang Zhang},
  journal={Philosophical Transactions of the Royal Society B},
Biramous appendages are a common feature among modern marine arthropods that evolved deep in arthropod phylogeny. The branched appendage of Cambrian arthropods has long been considered as the ancient biramous limb, sparking numerous investigations on its origin and evolution. Here, we report a new arthropod, Erratus sperare gen. et sp. nov., from the Lower Cambrian (Stage 3, 520 Ma) Chengjiang biota of Yunnan, China, with unique trunk appendages formed of lateral anomalocaridid-type flaps and… 

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