Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

A Silurian armoured aplacophoran and implications for molluscan phylogeny

Nature volume 490, pages 94–97 (2012)Cite this article

Subjects

Abstract

The Mollusca is one of the most diverse, important and well-studied invertebrate phyla; however, relationships among major molluscan taxa have long been a subject of controversy1,2,3,4,5,6,7,8,9. In particular, the position of the shell-less vermiform Aplacophora and its relationship to the better-known Polyplacophora (chitons) have been problematic: Aplacophora has been treated as a paraphyletic or monophyletic group at the base of the Mollusca3,6,8, proximate to other derived clades such as Cephalopoda2,3,10, or as sister group to the Polyplacophora, forming the clade Aculifera1,5,7,11,12. Resolution of this debate is required to allow the evolutionary origins of Mollusca to be reconstructed with confidence. Recent fossil finds13,14,15,16 support the Aculifera hypothesis, demonstrating that the Palaeozoic-era palaeoloricate ‘chitons’ included taxa combining certain polyplacophoran and aplacophoran characteristics5. However, fossils combining an unambiguously aplacophoran-like body with chiton-like valves have remained elusive. Here we describe such a fossil, Kulindroplax perissokomos gen. et sp. nov., from the Herefordshire Lagerstätte17,18 (about 425 million years bp), a Silurian deposit preserving a marine biota18 in unusual three-dimensional detail. The specimen is reconstructed three-dimensionally through physical–optical tomography19. Phylogenetic analysis indicates that this and many other palaeoloricate chitons are crown-group aplacophorans.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Oxford University Museum of Natural History (OUMNH) C.29641: holotype of Kulindroplax perissokomos.
Figure 2: Summary of parsimony analysis results.

Similar content being viewed by others

References

  1. Kocot, K. M. et al. Phylogenomics reveals deep molluscan relationships. Nature 477, 452–456 (2011)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  2. Wilson, N. G., Rouse, G. W. & Giribet, G. Assessing the molluscan hypothesis Serialia (Monoplacophora + Polyplacophora) using novel molecular data. Mol. Phylogenet. Evol. 54, 187–193 (2010)

    Article  PubMed  Google Scholar 

  3. Giribet, G. et al. Evidence for a clade composed of molluscs with serially repeated structures: monoplacophorans are related to chitons. Proc. Natl Acad. Sci. USA 103, 7723–7728 (2006)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  4. Passamaneck, Y. J., Schander, C. & Halanych, K. M. Investigation of molluscan phylogeny using large-subunit and small-subunit nuclear rRNA sequences. Mol. Phylogenet. Evol. 32, 25–38 (2004)

    Article  CAS  PubMed  Google Scholar 

  5. Sigwart, J. D. & Sutton, M. D. Deep molluscan phylogeny: synthesis of palaeontological and neontological data. Proc. R. Soc. B 274, 2413–2419 (2007)

    Article  PubMed  PubMed Central  Google Scholar 

  6. Salvini-Plawen, L. & Steiner, G. in Origin and Evolutionary Radiation of the Mollusca (ed. Taylor, J. D.), Ch. 2 29–51 (Oxford Univ. Press, 1996)

    Google Scholar 

  7. Scheltema, A. H. Aplacophora as progenetic aculiferans and the coelomate origin of mollusks as the sister taxon of Sipuncula. Biol. Bull. 184, 57–78 (1993)

    Article  CAS  PubMed  Google Scholar 

  8. Salvini-Plawen, L. On the phylogenetic significance of the aplacophoran Mollusca. Iberus 21, 67–97 (2003)

    Google Scholar 

  9. Telford, M. J. & Budd, G. E. Invertebrate evolution: bringing order to the molluscan chaos. Curr. Biol. 21, R964–R966 (2011)

    Article  CAS  PubMed  Google Scholar 

  10. Meyer, A., Witek, A. & Lieb, B. Selecting ribosomal protein genes for invertebrate phylogenetic inferences: how many genes to resolve the Mollusca? Methods Ecol. Evol. 2, 34–42 (2011)

    Article  Google Scholar 

  11. Vinther, J., Sperling, E. A., Briggs, D. E. G. & Peterson, K. A molecular palaeobiological hypothesis for the origin of aplacophoran molluscs and their derivation from chiton-like ancestors. Proc. R. Soc. B 279, 1259–1268 (2012)

    Article  PubMed  Google Scholar 

  12. Smith, S. A. et al. Resolving the evolutionary relationships of molluscs with phylogenomic tools. Nature 480, 364–367 (2011)

    Article  ADS  CAS  PubMed  Google Scholar 

  13. Sutton, M. D., Briggs, D. E. G., Siveter, J. & Siveter, J. An exceptionally preserved vermiform mollusc from the Silurian of England. Nature 410, 461–463 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  14. Sutton, M. D., Briggs, D. E. G., Siveter, J. & Siveter, J. Computer reconstruction and analysis of the vermiform mollusc Acaenoplax hayae from the Herefordshire Lagerstätte (Silurian, England), and implications for molluscan phylogeny. Palaeontology 47, 293–318 (2004)

    Article  Google Scholar 

  15. Vendrasco, M. J., Wood, T. E. & Runnegar, B. N. Articulated Palaeozoic fossil with 17 plates greatly expands disparity of early chitons. Nature 429, 288–291 (2004)

    Article  ADS  CAS  PubMed  Google Scholar 

  16. Sutton, M. D. & Sigwart, J. D. A chiton without a foot. Palaeontology 55, 401–411 (2012)

    Article  Google Scholar 

  17. Briggs, D. E. G., Siveter, J. & Siveter, J. Soft-bodied fossils from a Silurian volcaniclastic deposit. Nature 382, 248–250 (1996)

    Article  ADS  CAS  Google Scholar 

  18. Briggs, D. E. G., Siveter, J., Siveter, J. & Sutton, M. D. Virtual fossils from a 425 million-year-old volcanic ash. Am. Sci. 96, 474–481 (2008)

    Article  Google Scholar 

  19. Sutton, M. D. Tomographic techniques for the study of exceptionally preserved fossils. Proc. R. Soc. B 275, 1587–1593 (2008)

    Article  PubMed  PubMed Central  Google Scholar 

  20. Steiner, G. & Salvini-Plawen, L. Acaenoplax — polychaete or mollusc? Nature 414, 601 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  21. Sutton, M. D., Briggs, D. E. G., Siveter, J. & Siveter, J. Acaenoplax — polychaete or mollusc? (response to Steiner and Salvini-Plawen). Nature 414, 602 (2001)

    Article  ADS  CAS  Google Scholar 

  22. Cherns, L. Chelodes and closely related Polyplacophora (Mollusca) from the Silurian of Gotland, Sweden. Palaeontology 41, 545–573 (1998)

    Google Scholar 

  23. Donovan, S. K., Sutton, M. D. & Sigwart, J. D. Crinoids for lunch? An unexpected biotic interaction from the Upper Ordovician of Scotland. Geology 38, 935–938 (2010)

    Article  ADS  Google Scholar 

  24. Scheltema, A. H. & Ivanov, D. L. An aplacophoran postlarva with iterated dorsal groups of spicules and skeletal similarities to Paleozoic fossils. Invertebr. Biol. 121, 1–10 (2002)

    Article  Google Scholar 

  25. Farris, J. S. A successive approximations approach to character weighting. Syst. Zool. 18, 374–385 (1969)

    Article  Google Scholar 

  26. Goloboff, P. A. Estimating character weights during tree search. Cladistics 9, 83–91 (1993)

    Article  PubMed  Google Scholar 

  27. Conway Morris, S. & Caron, J.-B. Halwaxiids and the early evolution of the lophotrochozoans. Science 315, 1255–1258 (2007)

    Article  ADS  Google Scholar 

  28. McAlester, A. L. Systematics, affinities, and the life habits of Babinka, a traditional Ordovician lucinoid bivalve. Palaeontology 8, 231–246 (1965)

    Google Scholar 

  29. Sutton, M. D., Garwood, R. J., Siveter, J. & Siveter, J. SPIERS and VAXML; a software toolkit for tomographic visualisation and a format for virtual specimen interchange. Palaeontologia Electronica 15, http://palaeo-electronica.org/content/94-issue-2-2012-technical-articles/226-virtual-palaeontology-toolkit (2012)

Download references

Acknowledgements

The Natural Environmental Research Council (NERC Grant NE/F018037/1) supported this research. K. Saunders, K. Davies, C. Dean, D. Legg and C. Lewis provided technical assistance, and the staff of Tarmac Western and the late R. Fenn facilitated the fieldwork.

Author information

Authors and Affiliations

  1. Department of Earth Sciences and Engineering, Imperial College London, London SW7 2BP, UK,

    Mark D. Sutton

  2. Department of Geology & Geophysics, and Yale Peabody Museum of Natural History, Yale University, PO Box 208109, New Haven, Connecticut 06520-8109, USA,

    Derek E. G. Briggs

  3. Department of Geology, University of Leicester, Leicester LE1 7RH, UK,

    David J. Siveter

  4. Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK,

    Derek J. Siveter

  5. Geological Collections, University Museum of Natural History, Oxford OX1 3PW, UK,

    Derek J. Siveter

  6. Queen’s University Belfast, School of Biological Sciences, Marine Laboratory, Portaferry, Northern Ireland BT22 1PF, UK,

    Julia D. Sigwart

Authors
  1. Mark D. Sutton
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Derek E. G. Briggs
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. David J. Siveter
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Derek J. Siveter
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Julia D. Sigwart
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

D.J.S., D.J.S., D.E.G.B. and M.D.S. carried out fieldwork. M.D.S. and J.D.S. performed phylogenetic analyses. M.D.S reconstructed the specimen and wrote the paper, with scientific and editorial input from all other authors.

Corresponding author

Correspondence to Mark D. Sutton.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

This file contains Supplementary Notes 1-4, which includes Supplementary Figures, Tables and References, and full details for the Supplementary Data 1-2 files (see separate files for Supplementary Data). (PDF 686 kb)

Supplementary Data 1 (1)

The model is provided as four separate zip archive files to comply with Nature Publishing Group restrictions on the size of individual online files. See Supplementary Information for details on how to view this dataset. (ZIP 27720 kb)

Supplementary Data 1 (2)

The model is provided as four separate zip archive files to comply with Nature Publishing Group restrictions on the size of individual online files. See Supplementary Information for details on how to view this dataset. (ZIP 29196 kb)

Supplementary Data 1 (3)

The model is provided as four separate zip archive files to comply with Nature Publishing Group restrictions on the size of individual online files. See Supplementary Information for details on how to view this dataset. (ZIP 29196 kb)

Supplementary Data 1 (4)

The model is provided as four separate zip archive files to comply with Nature Publishing Group restrictions on the size of individual online files. See Supplementary Information for details on how to view this dataset. (ZIP 27637 kb)

Supplementary Data 2 (1)

Raw serial images (tomograms) of Kulindroplax perissokomos (OUMNH C. 29641) are presented here as highly compressed JPEGs split over two zip archives. (ZIP 18075 kb)

Supplementary Data 2 (2)

Raw serial images (tomograms) of Kulindroplax perissokomos (OUMNH C. 29641) are presented here as highly compressed JPEGs split over two zip archives. (ZIP 12714 kb)

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

Sutton, M., Briggs, D., Siveter, D. et al. A Silurian armoured aplacophoran and implications for molluscan phylogeny. Nature 490, 94–97 (2012). https://doi.org/10.1038/nature11328

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature11328

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing