Hostname: page-component-8678677fb7-z882p Total loading time: 0 Render date: 2026-10-13T04:37:28.351Z Has data issue: false hasContentIssue false
  • English
  • Français

An Early Cambrian radula

Published online by Cambridge University Press:  20 May 2016

Nicholas J. Butterfield
Nicholas J. Butterfield*
Affiliation:
Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK,
Get access Rights & Permissions [Opens in a new window]

Abstract

Microscopic teeth isolated from the early Cambrian Mahto Formation, Alberta, Canada, are identified as components of a molluscan radula, the oldest on record. Tooth-rows are polystichous and lack a medial rachidian tooth-column. Anterior-posterior differences in tooth-row morphology are interpreted as ontogenetic and correspond broadly to the diversity of isolated teeth, some of which correspond closely with those of extant aplacophoran molluscs. Associated pock-marked cuticular fragments are interpreted as having supported multiple biomineralized sclerites/spines in the manner of a modern chiton girdle. On the assumption that the cuticle and radula derive from the same species, there is a strong case for identifying this fossil as an aculiferan (aplacophoran + polyplacophora) mollusc, possibly a stem-group chiton. Similarities between the Mahto radula and the feeding apparatus of Wiwaxia and Odontogriphus are shown to be superficial. Terminal wear on some of the Mahto teeth indicate that they were used to scrape hard-substrates.

Information

Type
Research Article
Information
Journal of Paleontology , Volume 82 , Issue 3 , May 2008 , pp. 543 - 554
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Beedham, G. E. and Trueman, E. R. 1967. The relationship of the mantle and shell of the Polyplacophora in comparison with that of other Mollusca. Journal of Zoology, 151:215–231.CrossRefGoogle Scholar
Beedham, G. E. and Trueman, E. R. 1968. The cuticle of the Aplacophora and its evolutionary significance in the Mollusca. Journal of Zoology, 154: 443–451.Google Scholar
Bengtson, S. 1992. The cap-shaped Cambrian fossil Maikhanella and the relationship between coeloscleritophorans and molluscs. Lethaia, 25:401–420.Google Scholar
Bengtson, S. and Conway Morris, S. 1984. A comparative study of Lower Cambrian Halkieria and Middle Cambrian Wiwaxia. Lethaia, 17:307–329.Google Scholar
Bengtson, S. and Yue, Z. 1992. Predatorial borings in late Precambrian mineralized exoskeletons. Science, 257:367–369.Google Scholar
Brocco, S. L., O'Clair, R. M., and Cloney, R. A. 1974. Cephalopod integument: The ultrastructure of Kölliker's organs and their relationship to chaetae. Cell Tissue Research, 151:293–308.Google Scholar
Butterfield, N. J. 1990. A reassessment of the enigmatic Burgess Shale fossil Wiwaxia corrugata (Matthew) and its relationship to the polychaete Canadia spinosa Walcott. Paleobiology, 16:287–303.CrossRefGoogle Scholar
Butterfield, N. J. 2001. Cambrian food webs, p. 40–43. In Briggs, D. E. G. and Crowther, P. R. (eds.), Paleobiology II, A Synthesis. Blackwell Scientific, Oxford.Google Scholar
Butterfield, N. J. 2003. Exceptional fossil preservation and the Cambrian Explosion. Integrative and Comparative Biology, 43:166–177.CrossRefGoogle ScholarPubMed
Butterfield, N. J. 2005. Reconstructing a complex early Neoproterozoic eukaryote, Wynniatt Fm., arctic Canada. Lethaia, 38:155–169.Google Scholar
Butterfield, N. J. 2006. Hooking some stem-group “worms”: Fossil lophotrochozoans in the Burgess Shale. BioEssays, 29:1–6.Google Scholar
Butterfield, N. J. 2007. Macroecovolution and macroecology through deep time. Palaeontology, 50:41–55.Google Scholar
Caron, J.-B., Scheltema, A., Schander, C., and Rudkin, D. 2006. A soft-bodied mollusc with radula from the Middle Cambrian Burgess Shale. Nature, 442:159–163.Google Scholar
Caron, J.-B., Scheltema, A., Schander, C., and Rudkin, D. 2007. Reply to Butterfield on stem-group “worms”: Fossil lophotrochozoans in the Burgess Shale. Bioessays, 29:200–202.Google Scholar
Cherns, L. 2004. Early Palaeozoic diversification of chitons (Polyplacophora, Mollusca) based on new data from the Silurian of Gotland, Sweden. Lethaia, 37:445–456.Google Scholar
Conway Morris, S. 1985. The Middle Cambrian metazoan Wiwaxia corrugata (Matthew) from the Burgess Shale and Ogygopsis Shale, British Columbia, Canada. Philosophical Transactions of the Royal Society of London B, 307:507–586.Google Scholar
Conway Morris, S. 2006. Darwin's dilemma: The realities of the Cambrian ‘explosion’. Philosophical Transactions of the Royal Society B, 361:1069–1083.CrossRefGoogle ScholarPubMed
Conway Morris, S. and Menge, Chen. 1991. Cambroclaves and paracarinachitids, early skeletal problematica from the Lower Cambrian of South China. Palaeontology, 34:357–397.Google Scholar
Conway Morris, S. and Peel, J. S. 1995. Articulated halkieriids from the Lower Cambrian of North Greenland and their role in early protostome evolution. Philosophical Transactions of the Royal Society of London B, 347:305–358.Google Scholar
Conway Morris, S. and Caron, J.-B. 2007. Halwaxiids and the early evolution of the lophotrochozoans. Science, 315:1255–1258Google Scholar
Doguzhaeva, L., Mapes, R. H., and Mutvei, H. 1997. Beaks and radulae of early Carboniferous goniatites. Lethaia, 30:305–313.Google Scholar
Eekhaut, I., McHugh, D., Mardulyn, P., Tiedemann, R., Monteyne, D., Jangoux, M., and Milinkovitch, Michel C. 2000. Myzostomida: A link between trochozoans and flatworms? Proceedings of the Royal Society of London B, 267:1383–1392.CrossRefGoogle Scholar
Eernisse, D. J. and Kerth, K. 1988. The initial stages of radular development in chitons (Mollusca: Polyplacophora). Malacologia, 28:95–103.Google Scholar
Eernisse, D. J. and Reynolds, P. D. 1994. Polyplacophora, p. 55–110. In Harrison, F. W. and Kohn, A. J. (eds.), Microscopic Anatomy of Invertebrates. Volume 5, Mollusca I. Wiley-Liss, New York.Google Scholar
Fritz, W. H. and Mountjoy, E. W. 1975. Lower and early Middle Cambrian formations near Mount Robson, British Columbia and Alberta. Canadian Journal of Earth Sciences, 12:119–131.CrossRefGoogle Scholar
Gabbot, S. E. 1999. Orthoconic cephalopods and associated fauna from the late Ordovician Soom Shale Lagerstätte, South Africa. Palaeontology, 42: 123–148.Google Scholar
Giribet, G., Okusu, A., Lindgren, A. R., Huff, S. W., Schrödl, M., and Nishiguchi, M. K. 2006. Evidence for a clade composed of molluscs with serially repeated structures: Monoplacophorans are related to chitons. Proceedings of the National Academy of Science, USA, 103:7723–7728.Google Scholar
Gordon, D. P. 1975. The resemblance of bryozoan gizzard teeth to ‘annelidlike’ chaetae. Acta Zoologica, 56:283–289.Google Scholar
Gosliner, T. M. 1994. Gastropoda: Opisthobranchia, p. 253–355. In Harrison, F. W. and Kohn, A. J. (eds.), Microscopic Anatomy of Invertebrates. Volume 5, Mollusca I. Wiley-Liss, New York.Google Scholar
Gubanov, A. P. and Peel, J. S. 2000. Cambrian monoplacophoran molluscs (Class Helcionelloida). American Malacological Bulletin, 15:139–145.Google Scholar
Guralnick, R. and Smith, K. 1999. Historical and biomechanical analysis of integration and dissociation in molluscan feeding, with special emphasis on the true limpets (Patellogastropoda: Gastropoda). Journal of Morphology, 241:175–195.Google Scholar
Gustus, R. M. and Cloney, R. A. 1972. Ultrastructural similarities between setae of brachiopods and polychaetes. Acta Zoologica, 53:229–233.Google Scholar
Haas, W. 1981. Evolution of calcareous hardparts in primitive molluscs. Malacologia, 21:403–418.Google Scholar
Harper, E. M. 2003. Assessing the importance of drilling predation over the Palaeozoic and Mesozoic. Palaeogeography, Palaeoclimatology, Palaeoecology, 201:185–198.Google Scholar
Hausen, H. 2005. Chaetae and chaetogenesis in polychaetes (Annelida). In Bartolomaeus, T. and Purschke, G. (eds.), Morphology, Molecules, Evolution and Phylogeny in Polychaeta and Related Taxa. Hydrobiologia, 535/536: 37–52.Google Scholar
Hickman, C. S. 1980. Gastropod radulae and the assessment of form in evolutionary paleontology. Paleobiology, 6:276–294.Google Scholar
Hickman, C. S. 1984. Implications of radular tooth-row functional integration for archaeogastropod systematics. Malacologia, 25:143–160.Google Scholar
Hoare, R. D. and Mapes, R. H. 1986. The polyplacophoran “Chiton” carbonarious Stevens, 1858, in North America and new related species. Journal of Paleontology, 60:627–635.Google Scholar
Hoffman, S. 1949. Studien über das Integument der Solenogastren nebst Bemerkungen über die Verwandtschaft zwischen den Solenogastren und Placophoren. Zoologiska Bidrag från Uppsala, 27:293–427.Google Scholar
Hou, X., Bergström, J., and Yang, J. 2006. Distinguishing anomalocaridids from arthropods and priapulids. Geological Journal, 41:259–269.Google Scholar
Hua, H., Pratt, B. R., and Zhang, L.-Y. 2003. Borings in Cloudina shells: Complex predator-prey dynamics in the terminal Proterozoic. Palaios, 18: 454–459.Google Scholar
Mehl, J. 1984. Radula und Fangarme bei Michelinoceras sp. aus dem Silur von Bolivien. Paläontologische Zeitschrift, 58:211–229.Google Scholar
Mischor, B. and Märkel, K. 1984. Histology and regeneration of the radula of Pomacea bridgesi (Gastropoda, Prosobranchia). Zoomorphology, 104: 42–66.Google Scholar
Novack-Gottshall, P. M. and Miller, A. I. 2003. Comparative geographic and environmental diversity dynamics of gastropods and bivalves during the Ordovician Radiation. Paleobiology, 29:576–604.Google Scholar
Passamaneck, Y. J., Schander, C., and Halanych, K. M. 2004. Investigation of molluscan phylogeny using large-subunit and small-subunit nuclear rRNA sequences. Molecular Phylogenetics and Evolution, 32:25–38.Google Scholar
Peterson, K. J. and Eernisse, D. J. 2001. Animal phylogeny and the ancestry of bilaterians: Inferences from morphology and 18S rDNA gene sequences. Evolution and Development, 3:170–205.Google Scholar
Pojeta, J Jr., Eernisse, D. J., Hoare, R. D., and Henderson, M. D. 2003. Echinochiton dufoei: A new spiny Ordovician chiton. Journal of Paleontology, 77:646–654.Google Scholar
Runham, N. W. and Thornton, P. R. 1967. Mechanical wear of the gastropod radula: A scanning electron microscope study. Journal of Zoology, 153: 445–452.Google Scholar
Salvini-Plawen, L. v. 1981. The mollusan digestive system in evolution. Malacologia, 21:371–401.Google Scholar
Salvini-Plawen, L. v. 1985. Early evolution and the primitive groups, p. 59–150. In Trueman, E. R. and Clarke, M. R. (eds.), The Mollusca. Volume 10, Evolution. Academic Press, Orlando.Google Scholar
Salvini-Plawen, L. v. 1988. The structure and function of molluscan digestive systems, p. 301–379. In Trueman, E. R. and Clarke, M. R. (eds.), The Mollusca. Volume 11, Form and Function. Academic Press, London.Google Scholar
Scheltema, A. H. 1981. Comparative morphology of the radulae and alimentary tracts in the Aplacophora. Malacologia, 20:361–383.Google Scholar
Scheltema, A. H. 1993. Aplacophora as progenetic aculiferans and the coelomate origin of mollusks as sister taxon of Sipuncula. Biological Bulletin, 184:57–78.Google Scholar
Scheltema, A. H. 1999. Two solenogaster molluscs, Ocheyoherpia tracia n.sp. from Macquarie Island and Tegulaherpia tasmanica Salvini-Plawen from Bass Strait (Aplacophora: Neomeniomorpha). Records of the Australian Museum, 51:23–31.Google Scholar
Scheltema, A. H. and Ivanov, D. L. 2002. An aplacophoran postlarva with iterated dorsal groups of spicules and skeletal similarities to Paleozoic fossils. Invertebrate Biology, 121:1–10.Google Scholar
Scheltema, A. H., Kerth, K., and Kuzirian, A. M. 2003. Original molluscan radula: Comparisons among aplacophora, polyplacophora, gastropoda, and the Cambrian fossil Wiwaxia corrugata. Journal of Morphology, 257: 219–245.Google Scholar
Scheltema, A. H. and Schander, C. 2000. Discrimination and phylogeny of solenogaster species through the morphology of hard parts (Mollusca, Aplacophora, Neomeniomorpha). Biological Bulletin, 198:121–151.Google Scholar
Seilacher, A., Grazhdankin, D., and Legouta, A. 2003. Ediacaran biota: The dawn of animal life in the shadow of giant protists. Paleontological Research, 7:43–54.Google Scholar
Sirenko, B. I. 1997. The importance of the development of articulamentum for taxonomy of chitons (Mollusca, Polyplacophora). Ruthenica, 7:1–24.Google Scholar
Solem, A. and Richardson, E. S. 1975. Paleocadmus, a nautiloid cephalopod radula from the Pennsylvanian Francis Creek Shale of Illinois. The Veliger, 17:233–242.Google Scholar
Stankiewicz, B. A., Briggs, D. E. G., Evershed, R. P., Flannery, M. B., and Wuttke, M. 1997. Preservation of chitin in 25-million-year-old-fossils. Science, 276:1541–1543.Google Scholar
Steiner, G. and Salvini-Plawen, L. 2001. Acaenoplax—polychaete or mollusc? Nature, 414:601–602.Google Scholar
Strother, P. K., Wood, G. D., Taylor, W. A., and Beck, J. H. 2004. Middle Cambrian cryptospores and the origin of land plants. Association of Australasian Palaeontologists, Memoirs, 29:99–113.Google Scholar
Sutton, M. D., Briggs, D. E. G., Siveter, D. J., and Siveter, D. J. 2004. 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.Google Scholar
Sutton, M. D., Briggs, D. E. G., Siveter, D. J., and Siveter, D. J. 2006. Fossilized soft tissues in a Silurian platyceratid gastropod. Proceedings of the Royal Society B, 273:1039–1044.Google Scholar
Szaniawski, H. 2002. New evidence for the protoconodont origin of chaetognaths. Acta Palaeontologica Polonica, 473:405–419.Google Scholar
Tzetlin, A. B. 2004. Ultrastructural study of the jaw structures in two species of Ampharetidae (Annelida: Polychaeta). Acta Zoologica, 85:171–180.Google Scholar
Tzetlin, A. and Purschke, G. 2005. Pharynx and intestine. In Bartolomaeus, T. and Purschke, G. (eds.), Morphology, Molecules, Evolution and Phylogeny in Polychaeta and Related Taxa. Hydrobiologia, 535/536:199–225.Google Scholar
Vannier, J., Steiner, M., Renvoisé, E., Hu, S.-X., and Casanova, J.-P. 2007. Early Cambrian origin of modern food webs: Evidence from predator arrow worms. Proceedings of the Royal Society B, 274:627–633.Google Scholar
Vendrasco, M. J., Wood, T. E., and Runnegar, B. N. 2004. Articulated Palaeozoic fossil with 17 plates greatly expands disparity of early chitons. Nature, 429:288–291.Google Scholar
Vinther, J. and Nielsen, C. 2005. The early Cambrian Halkieria is a mollusc. Zoologica Scripta, 34:81–89.Google Scholar
Voltzow, J. 1994. Gastropoda: Prosobranchia, p. 111–252. In Harrison, F. W. and Kohn, A. J. (eds.), Microscopic Anatomy of Invertebrates. Volume 5, Mollusca I. Wiley-Liss, New York.Google Scholar
Whittington, H. W. and Briggs, D. E. G. 1985. The largest Cambrian animal, Anomalocaris, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London B, 311:1–192.Google Scholar
Yochelson, E. L. and Richardson, E. S. Jr. 1979. Polyplacophoran molluscs of the Essex Fauna (Middle Pennsylvanian, Illinois), p. 321–332. In Nitecki, M. H. (ed.), Mazon Creek Fossils. Academic Press, New York.Google Scholar
Zhuravlev, A. Y. and Wood, R. A. 1996. Anoxia as the cause of the mid-early Cambrian (Botomian) extinction event. Geology, 24:311–314.Google Scholar