An early Cambrian craniate-like chordate

  title={An early Cambrian craniate-like chordate},
  author={Jun‐yuan Chen and Diying Huang and CHIA-WEI Li},
Since the identification of the Lower Cambrian Yunnanozoon as a chordate in 1995 (ref. 1), large numbers of complete specimens of soft-bodied chordates from the Lower Cambrian Maotianshan Shale in central Yunnan (southern China) have been recovered. Here we describe a recently discovered craniate-like chordate, Haikouella lanceolata, from 305 fossil specimens in Haikou near Kunming. This 530 million-year-old (Myr) fish-like animal resembles the contemporaneous Yunnanozoon from the Chengjiang… 
Pikaia gracilens Walcott, a stem‐group chordate from the Middle Cambrian of British Columbia
The Middle Cambrian Pikaia gracilens (Walcott) has an iconic position as a Cambrian chordate, but until now no detailed description has been available and its relationships to both extant and extinct chordates and other deuterostomes are explored.
The first tunicate from the Early Cambrian of South China
Based on new, more complete “Cheungkongella” specimens that show branching tentacles, this form may be a lophophorate, and in any case is not a tunicate.
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These nested body plans portray a novel big picture of pararthropod evolution as a progression of step-wise changes both in the head and the appendages of Panarthropoda.
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Haikouella agrees so closely with recent predictions about pre‐craniates that the difficult problem of craniate origins is nearly solved.
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The main objective of this review is to examine the Cambrian diversity of these two deuterostome groups, the chordates and the vetulicolians, which are of particular interest because of the link to vertebrates, andBecause of the enigmatic nature of vetULicolians.
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Comparative study with the cephalochordate amphioxus suggests that precraniate evolution is marked by a series of innovations including: muscular ventilation with gill‐bearing and jointed brachial arches, paired head sensorial organs including paired eyes and nostrils, and some derivatives of neural crest cells.
Tentaculate Fossils from the Cambrian of Canada (British Columbia) and China (Yunnan) Interpreted as Primitive Deuterostomes
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A cladistic analysis showed the character interpretations of CMC are consistent with their wide-ranging evolutionary scenario, but that these interpretations leave unresolved the position of Pikaia within chordates.
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The oldest known chordate, Yunnanozoon lividum Hou et al. 1991, from the Chengiang Lagerstatte of Yunnan shows several features in its anatomy that had not been expected to occur at this stage of
A possible Early Cambrian chordate
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