Hostname: page-component-7b9c58cd5d-nzzs5 Total loading time: 0 Render date: 2025-03-15T07:44:52.379Z Has data issue: false hasContentIssue false
  • English
  • Français

Relationships of Cambrian Arachnata and the systematic position of Trilobita

Published online by Cambridge University Press:  20 May 2016

Gregory D. Edgecombe  and
Lars Ramsköld
Gregory D. Edgecombe
Affiliation:
Centre for Evolutionary Research, Australian Museum, 6 College Street, Sydney South, NSW 2000, Australia
Lars Ramsköld
Affiliation:
Museum of Palaeontology, University of Uppsala, Norbyvägen 22, S-752 36 Uppsala, Sweden
Get access Rights & Permissions [Opens in a new window]

Abstract

Cladistic relationships of Trilobita, Naraoiidae (five ingroup taxa), Helmetiida (five ingroup taxa), Xandarellida, and the Cambrian arachnates Retifacies, Sinoburius, Emeraldella, and Sidneyia are investigated based on 29 characters. Documentation of appendage morphology and other ventral structures in Saperion from the Chengjiang fauna permits an appraisal of helmetiid relationships. A monophyletic Trilobita [=“Olenellida” (Emuellida + Eutrilobita)] is defined by numerous synapomorphies, including exoskeletal calcification and dorsal eyes with calcified lenses and circumocular sutures. Helmetiida is a robust clade, resolved as (Helmetiidae (Tegopeltidae (Saperiidae + Skioldiidae))). Naraoiid monophyly is well-supported, but neither a naraoiid-trilobite nor a naraoiid-Retifacies clade are parsimonious, the latter grouping (“Nectopleura”) being explicitly paraphyletic. A sister group relationship between Xandarellida and Sinoburius is endorsed, although character support is novel compared to previous groupings of these taxa. The fourth postantennal limb pair in trilobites, naraoiids, and apparently helmetiids is based beneath the cephalothoracic articulation. Reweighted characters favor Trilobita and Helmetiida as closest relatives, with Petalopleura and then Naraoiidae as sister groups.

Type
Research Article
Information
Journal of Paleontology , Volume 73 , Issue 2: Papers from the Second International Trilobite Conference, August 1997 , March 1999 , pp. 263 - 287
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.)

References

Babcock, L. E. 1994. Systematics and phylogenetics of polymeroid trilobites from the Henson Gletscher and Kap Stanton formations (Middle Cambrian), North Greenland. Bulletin Gr⊘nlands geologiske Unders⊘gelse, 169:79–127.Google Scholar
Bergström, J. 1992. The oldest arthropods and the origin of the Crustacea. Acta Zoologica, 73:287–291.CrossRefGoogle Scholar
Bergström, J., and Brassel, G. 1984. Legs in the trilobite Rhenops from the Lower Devonian Hunsrück Slate. Lethaia, 17:67–72.CrossRefGoogle Scholar
Bergström, J., and Hou, X.-G. 1998. Chengjiang arthropods and their bearing on early arthropod evolution, p. 151–184. In Edgecombe, G. D. (ed.), Arthropod Fossils and Phylogeny. Columbia University Press, New York.Google Scholar
Briggs, D. E. G., Erwin, D. H., and Collier, F. J. 1994. The Fossils of the Burgess Shale. Smithsonian Institution Press, Washington, 238 p.Google Scholar
Bruton, D. L. 1981. The arthropod Sidneyia inexpectans, Middle Cambrian, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London, Series B, Biological Sciences, 295:619–656.Google Scholar
Budd, G. E. 1995. Kleptothule rasmusseni gen. et sp. nov.: an ?olenellinid-like trilobite from the Sirius Passet fauna (Buen Formation, Lower Cambrian), North Greenland. Transactions of the Royal Society of Edinburgh, Earth Sciences, 86:1–12.Google Scholar
Campbell, K. S. W. 1975. The functional morphology of Cryptolithus. Fossils and Strata, 4:65–86.CrossRefGoogle Scholar
Chen, J.-Y., and Zhou, G.-Q. 1997. Biology of the Chengjiang fauna, p. 11–105. In Chen, J.-Y., Chen, Y.-N. and Van Iten, H. (eds.) The Cambrian Explosion and the Fossil Record. Bulletin of the National Museum of Natural Science, 10. Taichung.Google Scholar
Chen, J.-Y., Edgecombe, G. D., and Ramsköld, L. 1997. Morphological and ecological disparity in naraoiids (Arthropoda) from the Early Cambrian Chengjiang fauna, China. Records of the Australian Museum, 49:1–24.Google Scholar
Chen, J.-Y., Ramsköld, L., and Zhou, G.-Q. 1995. Head segmentation in Early Cambrian Fuxianhuia: implications for arthropod evolution. Science, 268:1339–1343.Google Scholar
Chen, J.-Y., Zhou, G.-Q., and Ramsköld, L. 1995. The Cambrian lobopodian Microdictyon sinicum. Bulletin of the National Museum of Natural Science, Taichung, 5:1–93.Google Scholar
Chen, J.-Y., Zhou, G.-Q., Zhu, M.-Y., and Yeh, K.-Y. 1996. The Chengjiang Biota. A Unique Window of the Cambrian Explosion. National Museum of Natural Science, Taichung, 222 p. (In Chinese)Google Scholar
Chlupáč, I. 1988. The enigmatic arthropod Duslia from the Ordovician of Czechoslovakia. Palaeontology, 31:611–620.Google Scholar
Chlupáč, I. 1995. Lower Cambrian arthropods from the Paseky Shale (Barrandian area, Czech Republic). Journal of the Czech Geological Society, 40:9–36.Google Scholar
Cisne, J. L. 1975. Anatomy of Triarthrus and the relationships of the Trilobita. Fossils and Strata, 4:45–63.CrossRefGoogle Scholar
Collins, D. 1986. Paradise revisited. Rotunda, Royal Ontario Museum, 19:30–39.Google Scholar
Conway Morris, S. (ed.). 1982. Atlas of the Burgess Shale. Palaeontological Association, London.Google Scholar
Delle Cave, L., and Simonetta, A. M. 1991. Early Palaeozoic arthropods and problems of arthropod phylogeny: with some notes on taxa of doubtful affinities, p. 189–244. In Simonetta, A. M. and Conway Morris, S. (eds.), The Early Evolution of the Metazoa and the Significance of Problematic Taxa. Cambridge University Press, Cambridge.Google Scholar
Dunlop, J. A., and Selden, P. A. 1997. The early history and phylogeny of the chelicerates, p. 221–235. In Fortey, R. A. and Thomas, R. H. (eds.), Arthropod Relationships. Chapman & Hall, London.Google Scholar
Dzik, J., and Lendzion, K. 1988. The oldest arthropods of the East European Platform. Lethaia, 21:29–38.Google Scholar
Fortey, R. A., and Theron, J. N. 1994. A new Ordovician arthropod, Soomaspis, and the agnostid problem. Palaeontology, 37:841–861.Google Scholar
Fortey, R. A., and Whittington, H. B. 1989. The Trilobita as a natural group. Historical Biology, 2:125–138.Google Scholar
Geyer, G. 1996. The Moroccan fallotaspidid trilobites revisited. Beringeria, 18:89–199.Google Scholar
Hahn, G. 1989. Reconstruction of the phylogenetic relationships among the higher taxa of trilobites. Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg, 28:187–199.Google Scholar
Hammann, W., Laske, R., and Pillola, G. L. 1990. Tariccoia arrusensis n. g. n. sp., an unusual trilobite-like arthropod. Rediscovery of the “phyllocarid” beds of Taricco (1922) in the Ordovician “Puddinga” sequence of Sardinia. Bolletino della Società Paleontologica Italiana, 29:163–178.Google Scholar
Hou, X.-G. 1987. Three new large arthropods from Lower Cambrian, Chengjiang, eastern Yunnan. Acta Palaeontologica Sinica, 26:272–285. (In Chinese, with English summary)Google Scholar
Hou, X.-G. 1993. The arthropod Naraoia from the Lower Cambrian Chengjiang fauna. Lundadagama i Historisk Geologi och Paleontologi, III, Abstracts:12.Google Scholar
Hou, X.-G., and Bergström, J. 1991. The arthropods of the Lower Cambrian Chengjiang fauna, with relationships and evolutionary significance, p. 179–187. In Simonetta, A. M. and Conway Morris, S. (eds.), The Early Evolution of the Metazoa and the Significance of Problematic Taxa. Cambridge University Press, Cambridge.Google Scholar
Hou, X.-G., and Bergström, J. 1997. Arthropods of the Lower Cambrian Chengjiang fauna, southwest China. Fossils and Strata, 45:1–116.Google Scholar
Hou, X.-G., Chen, J.-Y., and Lu, H.-Z. 1989. Early Cambrian new arthropods from Chengjiang, Yunnan. Acta Palaeontologica Sinica, 28:42–57. (In Chinese, with English summary)Google Scholar
Hou, X.-G., Ramsköld, L., and Bergström, J. 1991. Composition and preservation of the Chengjiang fauna—a Lower Cambrian soft-bodied biota. Zoologica Scripta, 20:395–411.Google Scholar
Lauterbach, K.-E. 1980. Schlüsselereignisse in der Evolution der Grundplans der Arachnata (Arthropoda). Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg 23:163–327.Google Scholar
Lauterbach, K.-E. 1983. Synapomorphien zwischen Trilobiten- und Cheliceratenzweig der Arachnata. Zoologischer Anzeiger, 210:213–238.Google Scholar
Lauterbach, K.-E. 1989. Trilobites and phylogenetic systematics: a reply to G. Hahn. Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg 28:201–211.Google Scholar
Luo, H.-L., Hu, S.-X., Zhang, S.-S., and Tao, Y.-H. 1997. New occurrence of the Early Cambrian Chengjiang fauna in Haikou, Yunnan Province, and study on Trilobitoidea. Acta Geologica Sinica, 71:122–132.Google Scholar
Maddison, W. P., and Maddison, D. R. 1993. MacClade, version 3. Program and documentation. Sinauer Associates, Sunderland.Google Scholar
Minelli, A., and Bortoletto, S. 1988. Myriapod metamerism and arthropod segmentation. Biological Journal of the Linnean Society, 33:323–343.Google Scholar
Moore, R. C. 1959. Treatise on Invertebrate Paleontology, Pt. O, Arthropoda 1. Geological Society of America, University of Kansas Press, Lawrence, 560 p.Google Scholar
Müller, K. J., and Walossek, D. 1987. Morphology, ontogeny, and life habit of Agnostus pisiformis from the Upper Cambrian of Sweden. Fossils and Strata, 19, 124 p.Google Scholar
Patterson, C. 1982. Morphological characters and homology, p. 21–74. In Joysey, K. A. and Friday, A. E. (eds.), Problems of Phylogenetic Reconstruction. Academic Press, London.Google Scholar
Ramsköld, L., and Chen, J.-Y. 1998. Cambrian lobopodians: morphology and phylogeny, p. 107–150. In Edgecombe, G. D. (ed.), Arthropod Fossils and Phylogeny. Columbia University Press, New York.Google Scholar
Ramsköld, L., and Edgecombe, G. D. 1991. Trilobite monophyly revisited. Historical Biology, 4:267–283.Google Scholar
Ramsköld, L., and Edgecombe, G. D. 1996. Trilobite appendage structure—Eoredlichia revisited. Alcheringa, 20:269–276.Google Scholar
Ramsköld, L., Chen, J.-Y., Edgecombe, G. D., and Zhou, G.-Q. 1996. Preservational folds simulating tergite junctions in tegopeltid and naraoiid arthropods. Lethaia, 29:15–20.Google Scholar
Ramsköld, L., Chen, J.-Y., Edgecombe, G. D., and Zhou, G.-Q. 1997. Cindarella and the arachnate clade Xandarellida (Arthropoda, Early Cambrian) from China. Transactions of the Royal Society of Edinburgh, Earth Sciences, 88:19–38.Google Scholar
Rasetti, F. 1948. Cephalic sutures in Loganopeltoides and the origin of “Hypoparian” trilobites. Journal of Paleontology, 22:25–29.Google Scholar
Repina, L. N., and Okuneva, O. G. 1969. Kembrijskie chlenistonogie primor'ja. Paleontologicheskij Zhurnal, 1969:106–114.Google Scholar
Shergold, J. H. 1991. Protaspis and early meraspis growth stages of the eodiscoid trilobite Pagetia ocellata Jell, and their implications for classification. Alcheringa, 15:65–86.Google Scholar
Shu, D.-G., Geyer, G., Chen, L., and Zhang, X.-I. 1995. Redlichiacean trilobites with preserved soft-parts from the Lower Cambrian Chengjiang fauna (South China), p. 203–241. In Geyer, G. and Landing, E. (eds.), Morocco ‘95. The Lower-Middle Cambrian Standard of Western Gondwana. Beringeria Special Issue 2.Google Scholar
Simonetta, A. M., and Delle Cave, L. 1975. The Cambrian non trilobite arthropods from the Burgess Shale of British Columbia. A study of their comparative morphology, taxonomy, and evolutionary significance. Palaeontographia Italica, 69:1–37.Google Scholar
Størmer, L. 1944. On the relationships and phylogeny of fossil and recent Arachnomorpha. A comparative study on Arachnida, Xiphosurida, Eurypterida, Trilobita, and other fossil Arthropoda. Skrifter Utgitt av Det Norske Videnskaps-Akademi I Oslo, I. Matematisk-Naturvidenskapelig Klasse, 5:1–158.Google Scholar
Størmer, L. 1959. Trilobitoidea, p. O23–O37. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. O, Arthropoda 1. Geological Society of America, University of Kansas Press, Lawrence.Google Scholar
Stürmer, W., and Bergström, J. 1973. New discoveries on trilobites by X-rays. Paläontologische Zeitschrift, 47:104–141.Google Scholar
Stürmer, W., and Bergström, J. 1976. The arthropods Mimetaster and Vachonisia from the Devonian Hunsrück Shale. Paläontologische Zeitschrift, 50:78–111.Google Scholar
Swofford, D. L. 1993. PAUP: Phylogenetic Analysis Using Parsimony, Version 3.1. Program distributed by the Illinois Natural History Survey, Champaign.Google Scholar
Walcott, C. D. 1911. Middle Cambrian Merostomata. Cambrian Geology and Paleontology II. Smithsonian Miscellaneous Collections, 57:17–40.Google Scholar
Walcott, C. D. 1912. Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata. Cambrian Geology and Paleontology II. Smithsonian Miscellaneous Collections, 57:145–228.Google Scholar
Walcott, C. D. 1918. Geological explorations in the Canadian Rockies. Explorations and fieldwork of the Smithsonian Institution in 1917. Smithsonian Miscellaneous Collections, 68:4–20.Google Scholar
Walcott, C. D. 1931. Addenda to descriptions of Burgess Shale fossils. Smithsonian Miscellaneous Collections, 85:1–46 (with explanatory notes by Resser, C. E.).Google Scholar
Walossek, D. 1993. The Upper Cambrian Rehbachiella and the phylogeny of Branchiopoda and Crustacea. Fossils and Strata, 32:1–202.Google Scholar
Walossek, D., and Müller, K. J. 1990. Upper Cambrian stem-lineage crustaceans and their bearing upon the monophyletic origin of Crustacea and the position of Agnostus. Lethaia, 23:409–427.Google Scholar
Walossek, D., and Szaniawski, H. 1991. Cambrocaris baltica n. gen. n. sp., a possible stem-lineage crustacean from the Upper Cambrian of Poland. Lethaia, 24:363–378.Google Scholar
Whittington, H. B. 1975. Trilobites with appendages from the Middle Cambrian Burgess Shale, British Columbia. Fossils and Strata, 4:97–136.Google Scholar
Whittington, H. B. 1977. The Middle Cambrian trilobite Naraoia, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London, Series B, 280:409–443.Google Scholar
Whittington, H. B. 1980. Exoskeleton, moult stage, appendage morphology, and habits of the Middle Cambrian trilobite Olenoides serratus. Palaeontology, 23:171–204.Google Scholar
Whittington, H. B. 1985. Tegopelte gigas, a second soft-bodied trilobite from the Burgess Shale, Middle Cambrian, British Columbia. Journal of Paleontology, 59:1251–1274.Google Scholar
Whittington, H. B. 1993a. Anatomy of the Ordovician trilobite Placoparia. Philosophical Transactions of the Royal Society of London, Series B, 339:109–118.Google Scholar
Whittington, H. B. 1993b. Morphology, anatomy and habits of the Silurian homalonotid trilobite Trimerus. Memoirs of the Association of Australasian Palaeontologists, 15:69–83.Google Scholar
Whittington, H. B., and Almond, J. E. 1987. Appendages and habits of the Upper Ordovician trilobite Triarthrus eatoni. Philosophical Transactions of the Royal Society of London, Series B, 317:1–46.Google Scholar
Wills, M. A., Briggs, D. E. G., and Fortey, R. A. 1994. Disparity as an evolutionary index: a comparison of Cambrian and Recent arthropods. Paleobiology, 20:93–130.CrossRefGoogle Scholar
Wills, M. A., Briggs, D. E. G., Fortey, R. A., Wilkinson, M., and Sneath, P. H. A. 1998. An arthropod phylogeny based on fossil and Recent taxa, p. 33–105. In Edgecombe, G. D. (ed.), Arthropod Fossils and Phylogeny. Columbia University Press, New York.Google Scholar
Zhang, W.-T., and Hou, X.-G. 1985. Preliminary notes on the occurrence of the unusual trilobite Naraoia in Asia. Acta Palaeontologica Sinica, 24:591–595. (In Chinese, with English summary)Google Scholar