Xenoturbella is a deuterostome that eats molluscs

@article{Bourlat2003XenoturbellaIA,
  title={Xenoturbella is a deuterostome that eats molluscs},
  author={Sarah J. Bourlat and Claus Nielsen and Anne E. Lockyer and D. Timothy J. Littlewood and Maximilian J. Telford},
  journal={Nature},
  year={2003},
  volume={424},
  pages={925-928}
}
Xenoturbella bocki, first described in 1949 (ref. 1), is a delicate, ciliated, marine worm with a simple body plan: it lacks a through gut, organized gonads, excretory structures and coelomic cavities. Its nervous system is a diffuse nerve net with no brain. Xenoturbella's affinities have long been obscure and it was initially linked to turbellarian flatworms. Subsequent authors considered it variously as related to hemichordates and echinoderms owing to similarities of nerve net and epidermal… Expand
After all: Xenoturbella is an acoelomorph!
  • C. Nielsen
  • Biology, Medicine
  • Evolution & development
  • 2010
TLDR
A study of the musculature led Ehlersand Sopott-Ehlers (1997) to place Xenoturbella as the sistertaxon of all other bilaterians, and the morphological evidence seems to be overwhelming. Expand
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  • Biology, Medicine
  • Zoological Letters
  • 2015
TLDR
Although recent studies have uncovered many new and crucial facts regarding Xenoturbella, some fundamental biological information, such as phylogeny, complete life cycle, and genome, remain unsolved. Expand
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TLDR
The phylogenetic position for Xenoturbella is considered in the light of what is known of its genetics, morphology, and ontogeny and what light this might shine on the common ancestor of the deuterostomes and hence on the origins of the chordates. Expand
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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Xenoturbella bocki exhibits direct development with similarities to Acoelomorpha
TLDR
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Computational analysis of gene content in Xenacoelomorpha
TLDR
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References

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New light on the enigmatic Xenoturbella (phylum uncertain): ontogeny and phylogeny
  • O. Israelsson
  • Biology
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1999
TLDR
The previously unknown embryology of Xenoturbella is reported here that unequivocally corroborates a bivalve relationship and thus once and for all dismisses the potential new phylum plesiomorphic phylum. Expand
The ciliated epidermis of Xenoturbella bocki (Platyhelminthes, Xenoturbellida) with some phylogenetic considerations
TLDR
The epidermis of Xenoturbella bocki Westblad was studied by scanning and transmission electron microscopy and showed a characteristic pattern of axonemal filament termination in the distal tips of their cilia, which may be an apomorphic feature which indicates a close relationship between xenoturbellida, Nemertoder‐matida and Acoela. Expand
The epidermal ciliary rootlets of Xenoturbella bocki (Xenoturbellida) revisited: new support for a possible kinship with the Acoelomorpha (Platyhelminthes)
TLDR
The phylogenetic affinities of Xenoturbella remain highly debateable and a review of recent reports is given, together with a discussion of combinations of current phylogeny hypotheses. Expand
⃛and molluscan embryogenesis
TLDR
A study of oogenesis in X. bocki is reported, which contradicts earlier hypotheses as to the phylogeny of the animal and instead suggests a molluscan relationship close to or within the protobranch bivalves. Expand
Ultrastructure of the subepidermal musculature of Xenoturbella bocki, the adelphotaxon of the Bilateria
TLDR
Xenoturbella bocki is hypothesized to be the sister taxon of the Bilateria, the high-ranked taxon Xenoturbellida that lives on marine mud bottoms at a depth of 20–120 m and moves extremely slowly by ciliary gliding. Expand
Xenoturbella 's molluscan relatives⃛
TLDR
DNA sequence data are presented that place X. bocki within the protostome clade Eutrochozoa, and place it as the sister taxon of the Bilateria. Expand
Combined large and small subunit ribosomal RNA phylogenies support a basal position of the acoelomorph flatworms
TLDR
It is concluded that the Nemertodermatida and Acoela are basal bilaterians and, owing to their unique body plan and embryogenesis, should be recognized as a separate phylum, the Acoelomorpha. Expand
Fine Structural Observations on the Extracellular Matrix (ECM) of Xenoturbella bocki Westblad, 1949
TLDR
Previous indications of distinct similarities between certain characteristics of the epidermis and the SMC present in both enteropneusts and in Xenoturbella are strengthened. Expand
Fine Structure and Function of Pharynx Cilia in Glossobalanus minutus Kowalewsky (Enteropneusta)
TLDR
A model for mucus and water currents through gill slits is postulated and a ciliary specialization can be found in order to move a determinate substance, i.e. mucus or water. Expand
Changes in mitochondrial genetic codes as phylogenetic characters: two examples from the flatworms.
TLDR
A rapid computerized method for analyzing genetic codes is developed and demonstrated the wide phylogenetic distribution of the standard invertebrate code as well as confirming already known metazoan deviations from it (ascidian, vertebrate, echinoderm/hemichordate). Expand
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