Hallucigenia’s head and the pharyngeal armature of early ecdysozoans

@article{Smith2015HallucigeniasHA,
  title={Hallucigenia’s head and the pharyngeal armature of early ecdysozoans},
  author={Martin R. Smith and Jean‐Bernard Caron},
  journal={Nature},
  year={2015},
  volume={523},
  pages={75-78}
}
The molecularly defined clade Ecdysozoa comprises the panarthropods (Euarthropoda, Onychophora and Tardigrada) and the cycloneuralian worms (Nematoda, Nematomorpha, Priapulida, Loricifera and Kinorhyncha). These disparate phyla are united by their means of moulting, but otherwise share few morphological characters—none of which has a meaningful fossilization potential. As such, the early evolutionary history of the group as a whole is largely uncharted. Here we redescribe the 508-million-year… 
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Palaeontology: Hallucigenia's head
TLDR
Data is presented on newly examined 508-million-year-old fossils of Hallucigenia sparsa that at last reveal the head in some detail and provides concrete evidence of structures that might have existed in the last common ancestor of the Ecdysozoa.
Introvert and pharynx of Mafangscolex, a Cambrian palaeoscolecid
TLDR
New specimens of Mafangscolex from the Cambrian Stage 3 Xiaoshiba Lagerstätte in Kunming, China provide the first detailed account of a proboscis in Palaeoscoelcida sensu stricto, a core group of palaeos colecids characterized by having a tessellating scleritome of phosphatic plates and platelets.
Armored kinorhynch-like scalidophoran animals from the early Cambrian
TLDR
The fossil record confirms that all three scalidophoran phyla diverged no later than the Cambrian Period, including the new species Eokinorhynchus rarus and two unnamed but related forms.
Onychophoran-like myoanatomy of the Cambrian gilled lobopodian Pambdelurion whittingtoni
TLDR
It is shown that Pambdelurion's myoanatomy conforms closely to that of extant onychophorans, with unsegmented dorsal, ventral and longitudinal muscle groups in the trunk, and extrinsic and intrinsic muscles controlling the legs.
The mouth apparatus of the Cambrian gilled lobopodian Pambdelurion whittingtoni
TLDR
It is shown that the early Cambrian gilled lobopodian Pambdelurion whittingtoni from Sirius Passet, Greenland, possesses a mouth apparatus identical to Omnidens, being composed of the same three zones with detailed similarities of sclerites in each zone.
Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan
TLDR
This study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy, may have characterised the origin and radiation of crown group ecdysozoans from Acosmia -like ancestors.
Cambrian suspension-feeding lobopodians and the early radiation of panarthropods
TLDR
A Bayesian approach to cladistics supports the view that a semi-sessile, suspension-feeding lifestyle characterized the origin and rise of Panarthropoda from cycloneuralian body plans.
The functional head of the Cambrian radiodontan (stem-group Euarthropoda) Amplectobelua symbrachiata
TLDR
This study is the first description of appendicular structures other than the frontal appendages in the functional head region of radiodontans, revealing novel feeding structures in the morphological transition from the lower- to the upper- stem-group of Euarthropoda.
Waptia fieldensis Walcott, a mandibulate arthropod from the middle Cambrian Burgess Shale
TLDR
It is construe that Waptia was an active swimming predator of soft prey items, using its anterior appendages for food capture and manipulation, and also potentially for clinging to epibenthic substrates.
Discussion on ‘Tabelliscolex (Cricocosmiidae: Palaeoscolecidomorpha) from the early Cambrian Chengjiang Biota and the evolution of seriation in Ecdysozoa’ by Shi et al. 2021 (JGS, jgs2021-060)
Exceptionally preserved fossils are key to reconstructing the origin of the modern animal body plans in the Cambrian radiation. The Panarthropod phyla Euarthropoda, Onychophora and Tardigrada have…
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