Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-03T00:49:43.020Z Has data issue: false hasContentIssue false
  • English
  • Français

The aglaspidid arthropod Beckwithia from the Cambrian of Utah and Wisconsin

Published online by Cambridge University Press:  19 May 2016

Stephen P. Hesselbo
Stephen P. Hesselbo*
Affiliation:
Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, United Kingdom
Get access Rights & Permissions [Opens in a new window]

Abstract

New specimens of Beckwithia typa, from the upper Middle Cambrian of Utah, show that, contrary to previous descriptions, the animal had at least 10 tergites (possibly 12) and probably a tail-spine. There is no evidence for a fused tail-plate, the one character that made Beckwithia appear anomalous with respect to other aglaspidid arthropods. It did, however, differ from most other aglaspidids in having a single series of axial spines along the trunk, but this cannot be regarded as a basis for continued separation of Beckwithia into a monogeneric family. A possible relationship with Kodymirus vagans is suggested by the presence of axial spines, although there may have been significant differences in the nature of the ventral sclerites. Beckwithia? major from the Upper Cambrian of Wisconsin is known only from fragmentary specimens and no evidence of a fused tail-plate has been found. Beckwithia? daubikhensis from the Khanka Massif, Soviet Union, is unlikely to be a member of this genus; the single specimen on which the taxon was based may be a poorly preserved Khankaspis bazhanovi.

Type
Research Article
Information
Journal of Paleontology , Volume 63 , Issue 5 , September 1989 , pp. 636 - 642
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

Bengtson, P. 1988. Open nomenclature. Palaeontology, 31:223–227.Google Scholar
Bergström, J. 1979. Morphology of fossil arthropods as a guide to phylogenetic relationships, p. 3–56. In Gupta, A. P. (ed.), Arthropod Phylogeny. Van Nostrand Reinhold, New York.Google Scholar
Briggs, D. E. G., and Fortey, R. A. 1982. The cuticle of aglaspidid arthropods, a red-herring in the early history of vertebrates. Lethaia, 15:25–29.Google Scholar
Briggs, D. E. G., and Whittington, H. B. 1985. Modes of life of arthropods from the Burgess Shale, British Columbia. Transactions of the Royal Society of Edinburgh, 76:149–160.Google Scholar
Briggs, D. E. G., Bruton, D. L. and Whittington, H. B. 1979. Appendages of the arthropod Aglaspis spinifer (Upper Cambrian, Wisconsin) and their significance. Palaeontology, 22:167–180.Google Scholar
Caster, K. E., and Brooks, H. K. 1956. New fossils from the Canadian–Chazyan (Ordovician) hiatus in Tennessee. Bulletin of American Palaeontology, 36:157–199.Google Scholar
Chlupáč, I. 1965. Xiphosuran merostomes from the Ordovician of Bohemia. Sborník Geologických věd paleontologie, râda, P5:7–38.Google Scholar
Chlupáč, I., and Havlíček, V. 1965. Kodymirus n.g., an new aglaspid merostome of the Cambrian of Bohemia. Sborník Geologických věd paleontologie, râda, P6:7–20.Google Scholar
Graham, W. A. P. 1931. A new crustacean of the family Aglaspidae from the Upper Mississippi Valley. Ohio Journal of Science, 31(2):127–128.Google Scholar
Hall, J. 1862. On a new crustacean from the Potsdam Sandstone. Canadian Naturalist, 7:443–445.Google Scholar
Hesselbo, S. P. 1988. Trace fossils of Cambrian aglaspidid arthropods. Lethaia, 21:139–146.Google Scholar
Matthews, S. C. 1973. Notes on open nomenclature and on synonymy lists. Palaeontology, 16:713–720.Google Scholar
Miller, S. A. 1877. The American Paleozoic Fossils. Cincinnati, Ohio, 253 p.Google Scholar
Müller, K. J., and Walossek, D. 1985. A remarkable arthropod fauna from the Upper Cambrian “Orsten” of Sweden. Transactions of the Royal Society of Edinburgh, 76:161–172.Google Scholar
Raasch, G. O. 1939. Cambrian merostomata. Geological Society of America Special Paper 16, 146 p.Google Scholar
Radwanski, A., and Roniewicz, P. 1967. The trace fossil Aglaspididichnus sanctacrucensis n.gen., n.sp., a probable resting place of an aglaspid (Xiphosura). Acta Palaeontologica Polonica, 12:545–555.Google Scholar
Raw, F. 1957. Origin of chelicerates. Journal of Paleontology, 31:139–192.Google Scholar
Rees, M. N. 1986. A fault controlled trough through a carbonate platform: the Middle Cambrian House Range embayment. Geological Society of America Bulletin, 97:1054–1069.Google Scholar
Repina, L. N., and Okuneva, O. G. 1969. Cambrian arthropods of the Maritime Territory. Paleontological Journal, 3:95–103.Google Scholar
Resser, C. E. 1931. A new Middle Cambrian merostome crustacean. Proceedings of the United States National Museum 79, Article 33, 4 p.Google Scholar
Robison, R. A. 1984. Cambrian Agnostida of North America and Greenland; Part I, Ptychagnostidae. University of Kansas Paleontological Contributions, Paper, 109:1–59.Google Scholar
Størmer, L. 1944. On the relationships and phylogeny of fossil and Recent arachnomorpha. Skrifter utgitt av det Norske videnskspsakademi i Oslo. I. Matematisk-naturvidenskabelig klasse, 5:1–158.Google Scholar
Størmer, L. 1955. Chelicerata, Merostomata, p. 1–44. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. P, Arthropoda 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Størmer, L. 1959. Trilobitomorpha, Trilobitoidea, p. 022–037. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. O, Arthropoda 1. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Whittington, H. B. 1979. Early arthropods, their appendages and relationships, p. 253–268. In House, M. R. (ed.), The Origin of Major Invertebrate Groups. Systematics Association Special Publication 12.Google Scholar
Whittington, H. B. 1980. The significance of the fauna of the Burgess Shale, Middle Cambrian, British Columbia. Proceedings of the Geologists Association, 91:127–148.Google Scholar
Whittington, H. B. 1985. The Burgess Shale. Yale University Press, New Haven, 151 p.Google Scholar