Reinterpretation of Yunnanozoon as the earliest known hemichordate

@article{Shu1996ReinterpretationOY,
  title={Reinterpretation of Yunnanozoon as the earliest known hemichordate},
  author={De-gan Shu and X. Zhang and L. Chen},
  journal={Nature},
  year={1996},
  volume={380},
  pages={428-430}
}
THE Chengjiang fossil Lagerstätte is one of the earliest and most important palaeontological sites from the Phanerozoic era1,2, about 530 million years ago3. It yields extremely abundant and remarkably preserved soft-bodied fossils and shells with soft parts of various kinds, including bradoriids4–6, trilobites7,8, crustaceans9, brachiopods, worms, sponges, algae and many unknown forms10–13. One of these fossils is Yunnanozoon14, which we reinterpret here as the earliest known hemichordate… 
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101 Citations

Hemichordata (Pterobranchia, Enteropneusta) and the fossil record
  • J. Maletz
  • Geography, Environmental Science
  • 2014
The origins of graptolites and other pterobranchs: a journey from ‘Polyzoa’
TLDR
There is strong molecular evidence to indicate that lophophorates are very distant from hemichordates and echinoderms, in a different major branch of the animal phylogenetic tree, and there is weaker evidence that pterobranchs may be derived from acorn worms, and hence that the vermiform body plan may be ancestral within hemicordates.
A Pikaia-like chordate from the Lower Cambrian of China
TLDR
A single specimen of a Lower Cambrian chordate, Cathaymyrus diadexus, new genus and species, that is similar to Pikaia but predates it by about 10 million years (Myr).
Tracing the evolutionary origins of the Hemichordata (Enteropneusta and Pterobranchia)
  • J. Maletz
  • Geography, Environmental Science
    Palaeoworld
  • 2019
A pipiscid-like fossil from the Lower Cambrian of south China
TLDR
A possible pipiscid, a metazoan previously known only from the Upper Carboniferous, is described from the Lower Cambrian of south China, and this discovery from the Chengjiang fossil-Lagerstätte indicates that the assignment of pipiscids to the Agnatha deserves to be reconsidered.
New data on the palaeobiology of the enigmatic yunnanozoans from the Chengjiang Biota, Lower Cambrian, China
TLDR
This analysis reveals new details of the putative pharyngeal pores of Yunnanozoon lividum, and although there are similarities with the gill slits of deuterostomes, the question of their homology remains moot.
On the Phylum Vetulicolia
TLDR
Since all vetulicolians share similar characters in their anterior section (pharynx), and on the basis of differences in their posterior section, a new classification system is proposed, with a new class, the Heteromorphida erected.
New sites of Chengjiang fossils: crucial windows on the Cambrian explosion
Soft-bodied and lightly sclerotized Chengjiang fossils have been found at more than ten new localities in the Lower Cambrian Qiongzhusi and Canglangpu formations of east central Yunnan. At the same…
The earliest history of the deuterostomes: the importance of the Chengjiang Fossil-Lagerstätte
TLDR
The known diversity of Chengjiang deuterostomes are reviewed and it is argued that the vetulicolians and yunnanozoans represent very primitive deuterOSTomes, as well as new data to indicate that the yunncozoans are unlikely to be any sort of chordate.
Tentaculate Fossils from the Cambrian of Canada (British Columbia) and China (Yunnan) Interpreted as Primitive Deuterostomes
TLDR
The evidence is suggested that the evidence is more consistent with the ambulacraria being primitive deuterostomes, with specific comparisons being made to the pterobranch hemichordates and pre-radial echinoderms.
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