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2011 | 56 | 4 |

Tytuł artykułu

Soft anatomy of the Early Cambrian arthropod Isoxys curvirostratus from the Chengjiang biota of South China with a discussion on the origination of great appendages

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Warianty tytułu

Języki publikacji

EN

Abstrakty

EN
An updated reconstruction of the body plan, functional morphology and lifestyle of the arthropod Isoxys curvirostratusis proposed, based on new fossil specimens with preserved soft anatomy found in several localities of the Lower Cambrian Chengjiang Lagerstätte. The animal was 2–4 cm long and mostly encased in a single carapace which is folded dorsally without an articulated hinge. The attachment of the body to the exoskeleton was probably cephalic and apparently lacked any well−developed adductor muscle system. Large stalked eyes with the eye sphere consisting of two layers (as corneal and rhabdomeric structures) protrude beyond the anterior margin of the carapace. This feature, together with a pair of frontal appendages with five podomeres that each bear a stout spiny outgrowth, suggests it was raptorial. The following 14 pairs of limbs are biramous and uniform in shape. The slim endopod is composed of more than 7 podomeres without terminal claw and the paddle shaped exopod is fringed with at least 17 imbricated gill lamellae along its posterior margin. The design of exopod in association with the inner vascular (respiratory) surface of the carapace indicates I. curvirostratus was an active swimmer. Morphological comparisons demonstrate that species of Isoxys were diverse in feeding habits and occupied a very broad morphospace, i.e., carapace bivalved or a single shield, the pre−oral limbs antenniform or modified into great appendages, the succeeding endopods slim or stout. This casts doubt on the current taxonomy that assigns all species to a single genus, and on any presumed lifestyle of Isoxys extrapolated to the generic level. Finally, since I. curvirostratus and I. acutangulus carry a pair of great appendages, Isoxys has recently been placed into the great appendage arthropods. Such placement might be inadequate because the homology of the great appendages can not be established.

Słowa kluczowe

Wydawca

-

Rocznik

Tom

56

Numer

4

Opis fizyczny

p.843-852,fig.,ref.

Twórcy

autor
  • State Key Laboratory of Continental Dynamics, Early Life Institute and Department of Geology, Northwest University, Xian 710069, PR China
autor
  • State Key Laboratory of Continental Dynamics, Early Life Institute and Department of Geology, Northwest University, Xian 710069, PR China
autor
  • State Key Laboratory of Continental Dynamics, Early Life Institute and Department of Geology, Northwest University, Xian 710069, PR China

Bibliografia

  • Bergström, J. and Hou, X.−G. 2005. Early Palaeozoic non−lamellipedian arthropods. In: S. Koenemann and R.A. Jenner (eds.), Crustacea and Arthropod Relationships, 73–94. CRC Press, Taylor & Francis Group, Boca Raton, Florida.
  • Briggs, D.E.G., Erwin, D.H., and Collier, F.J. 1994. The Fossils of the Burgess Shale. 238pp. Smithsonian Institution Press, Washington.
  • Briggs, D.E.G., Lieberman, B.S., Hendricks, J.R., Halgedahl, S.L., and Jarrard, R.D. 2008. Middle Cambrian arthropods from Utah. Journal of Paleontology 82: 238–254.
  • Briggs, D.E.G., Sutton, M.D., Siveter, D.J., and Siveter, D.J. 2004. A new phyllocarid (Crustacea: Malacostraca) from the Silurian Fossil−Lagerstätte of Herefordshire, UK. Proceedings of the Royal Society of London B 271:131–138.
  • Brusca, R.C. and Brusca, G.J. 2003. Invertebrates. 936 pp. Sinauer Associates, Sunderland, Massachusetts.
  • Budd, G.E. 2002. A palaeontological solution to the arthropod head problem. Nature 417: 271–275.
  • Chen, J.−Y. 2004. The Dawn of Animal World [in Chinese]. 366 pp. Jiangsu Science and Technology Press, Chian.
  • Chen, J.−Y., Waloszek, D., and Maas, A. 2004. A new “great−appendage” arthropod from the Lower Cambrian of China and homology of chelicerate chelicerae and raptorial antero−ventral appendages. Lethaia 37: 3–20.
  • Chen, J.−Y., Waloszek, D., Maas, A., Braun, A., Huang, D.−Y., Wang, W.−Q., and Stein, M. 2007. Early Cambrian Yangtze Plate Maotianshan Shale macrofauna biodiversity and the evolution of predation. Palaeogeography, Palaeoclimatology, Palaeoecology 254: 250–272.
  • Chen, J.−Y., Zhou, G.−Q., Zhu, M.−Y., and Yeh, K.−Y. 1996. The Chengjiang Biota—A Unique Window of the Cambrian Explosion [in Chinese]. 222 pp. National Museum of Natural Science, Taichung.
  • Cotton, T.J. and Braddy, S.J. 2004. The phylogeny of arachnomorph arthropods and origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.
  • García−Bellido, D.C. and Collins, D.H. 2005. Isoxys with soft parts from the Middle Cambrian Burgess Shale.In: S.−C. Peng, M.−Y. Zhu, G.−X. Li, and H. Vaniten (eds.), Acta Micropalaeontologica Sinica 22 (Supplement), 50. Nanjing Institute of Geology and Palaeontology, Nanjing, China.
  • García−Bellido, D.C., Paterson, J.R., Edgecombe, G.D., Jago, J.B., Gehling, J.G., and Lee, M.S.Y. 2009a. The bivalved arthropods Isoxys and Tuzoia with soft−part preservation from the Lower Cambrian Emu Bay Shale Lagerstätte (Kangaroo Island, Australia).Palaeontology 52: 1221–1241.
  • García−Bellido, D.C., Vannier, J., and Collins, D. 2009b. Soft−part preservation in two species of the arthropod Isoxys from the middle Cambrian Burgess Shale of British Columbia, Canada. Acta Palaeontologica Polonica 54: 699–712.
  • Hou, X.−G. 1987a. Three new large arthropods from the Lower Cambrian, Chengjiang, eastern Yunnan [in Chinese]. Acta Palaeontologica Sinica 26: 272–285.
  • Hou, X.−G. 1987b. Two new arthropods from the Lower Cambrian, Chengjiang, eastern Yunnan [in Chinese]. Acta Palaeontologica Sinica 26: 236–256.
  • Hou, X.−G. 1999. New rare bivalved arthropods from the Lower Cambrian Chengjiang fauna, Yunnan, China. Journal of Paleontology 73: 102–116.
  • Hou, X.−G., Aldridge, R.J., Bergström, J., Siveter, D.J., and Feng, X.−H. 2004. The Cambrian Fossils of Chengjiang, China: The Flowering of Early Animal Life. 233 pp. Blackwell Science, Oxford.
  • Hou, X.−G. and Bergström, J. 1997. Arthropods of the Lower Cambrian Chengjiang fauna, Southwest China. Fossil and Strata 45: 1–116.
  • Hu, S.−X., Steiner, M., Zhu, M.−Y., Erdtmann, B.D., Luo, H.−L., and Chen, L.−Z. 2007. Diverse pelagic predators from the Chengjiang Lagerstätte and the establishment of modern−style pelagic ecosystems in the early Cambrian. Palaeogeography, Palaeoclimatology, Palaeoecology 254: 307–316.
  • Jiang, Z.−W. 1982. Small shelly fossils [in Chinese]. In: H.−L. Luo, Z.−W. Jiang, X.−C. Wu, X.−L. Song, and Y.−L. Ou (eds.), The Sinian–Cambrian Boundary in Eastern Yunnan, China, 163–199. People’s Publishing House of Yunnan, China.
  • Kühl, G., Briggs, D.E.G., and Rust, J. 2009. A great−appendage arthropod with a radial mouth from the Lower Devonian Hunsrück Slate, Germany. Science 323: 771–773.
  • Ramsköld, L., Chen, J.−Y., Edgecombe, G.D., and Zhou, G.−Q. 1997. Cindarella and the arachnate clade Xandarelllida (Arthropoda, Early Cambrian) from China. Transactions of the Royal Society of Edinburgh: Earth Sciences 88: 19–38.
  • Scholtz, G. and Edgecombe, G.D. 2006. The evolution of arthropod heads: reconciling morphological, developmental and palaeontological evidence. Development, Genes and Evolution 216: 395–415.
  • Shu, D.−G., Zhang, X.−L., and Geyer, G. 1995. Anatomy and systematic affinities of the Lower Cambrian bivalved arthropod Isoxys auritus. Alcheringa 19: 333–342.
  • Simonetta A.M. and Delle Cave, L.F. 1975. The Cambrian non trilobite arthropods from the Burgess Shale of British Columbia. A study of their comparative morphology, taxonomy and evolutionary significance. Paleontographia Italica 69 (New Series 39): 1–37.
  • Stein, M., Peel, J.S., Siveter, D.J., and Williams, M. 2010. Isoxys (Arthropoda) with preserved soft anatomy from the Sirius Passet Lagerstätte, Lower Cambrian of North Greeland. Lethaia 43: 258–265.
  • Vannier, J. and Chen, J.−Y. 2000. The Early Cambrian colonization of pelagic niches exemplified by Isoxys(Arthropoda). Lethaia 33: 295–311.
  • Vannier, J., García−Bellido, D.C., Hu, S.−X., and Chen, A.−L. 2009. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas. Proceedings of the Royal Society B 276: 2567–2574.
  • Vannier, J., Williams, M., and Siveter, D.J. 1997. The Cambrian origin of the circulatory system of crustaceans. Lethaia 30: 169–184.
  • Waloszek, D., Maas, A., Chen, J.−Y., and Stein, M. 2007. Evolution of cephalic feeding structures and the phylogeny of Arthropoda. Palaeogeography, Palaeoclimatology, Palaeoecology 254: 273–287.
  • Williams, M., Siveter, D.J., and Peel, J.S. 1996. Isoxys (Arthropoda) from the Early Cambrian Sirius Passet Lagerstätte, North Greenland. Journal of Paleontology 70: 947–954.
  • Zhang, X.−L. 2009. From limbs to jaws—the nature of the mouthparts of anomalocaridids. In: M.R. Smith, L.J. O’Brien, and J.−B. Caron (eds.), Abstract Volume of International Conference on the Cambrian Explosion, 60. Burgess Shale Consortium, Toronto.
  • Zhang, X.−L., Liu, W., and Zhao, Y.−L. 2008. Cambrian Burgess Shale−type Lagerstätten in South China: distribution and significance. Gondwana Research 14: 255–262.
  • Zhang, X.−L., Shu, D.−G., Li, Y., and Han, J. 2001. New sites of Chengjiang fossils: crucial windows on the Cambrian explosion. Journal of the Geological Society of London 158: 211–218.

Typ dokumentu

Bibliografia

Identyfikatory

Identyfikator YADDA

bwmeta1.element.agro-1e9e1453-0fae-4bc4-8670-2e5d451d792d
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