Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-20T03:29:48.820Z Has data issue: false hasContentIssue false

The Corynexochina (Trilobita): a poorly understood suborder

Published online by Cambridge University Press:  20 May 2016

Harry B. Whittington*
Affiliation:
Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, United Kingdom

Abstract

Trilobites of this suborder from Europe and North America have not been studied in detail, in contrast to the attention given to relationships within the orders Agnostida and Ptychopariina. The basis of the Corynexochina is the type species of Corynexochus from the middle Cambrian of Sweden. The type material redescribed here is only the cranidium, and is inadequate for diagnosis of the genus. A species attributed to this genus occurring in the Cambrian of southern France is represented by entire dorsal exoskeletons and is urgently in need of redescription. Similar material is recorded in northern Spain. Both complete exoskeletons and growth stages of Corynexochina have been described from Cambrian strata in Russia, Australia, Morocco and China, showing the wide geographical range and varied morphology of the Suborder. The type species of two genera from boulders of middle Cambrian age found in Quebec, Canada, are redescribed from exceptionally well preserved, though small, specimens. They appear to represent a distinct group related to some of the Zacanthoididae. Families of Corynexochina are inadequately discriminated one from another, so that a family name can only be used with question. Until this is remedied, diagnosis of a new group is not possible.

Type
Research Article
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

Alvaro, J. J., Vizcaino, D., and Vennin, E. 1999. Trilobite diversity patterns in the Middle Cambrian of southwestern Europe: a comparative study. Palaeogeography, Palaeoclimatology, Palaeoecology, 151:241254.CrossRefGoogle Scholar
Angelin, N. P. 1854. Palaeontologia Scandinavica, Pars. 1, Crustacea Formationis Transitionis, fasc. 2, p. 1ix, 21–92, pls. 25–41.Google Scholar
Buchholz, A. 1997. Trilobiten mittelkambrischer Geschiebe aus Mecklenburg und Vorpommerns (Norddeutschland). —Archiv Für Geschiebekunde 2:185264.Google Scholar
Courtessole, R. 1973. Le Cambrien Moyen de la Montagne Noire: Biostratigraphie, p. 1248, pls. 1–27. Imprimerie d'Oc, Toulouse, France.Google Scholar
Fortey, R. A. 2001. Trilobite systematics: The last 75 years. Journal of Paleontology, 75:11411151.2.0.CO;2>CrossRefGoogle Scholar
Geyer, G. 1994. Cambrian corynexochid trilobites from Morocco. Journal of Paleontology, 68:13061320.CrossRefGoogle Scholar
Grönwall, K. A. 1902. Bomholms Paradoxideslag og deres Fauna. Danmarks geologiske Undersøgelse, Series II, no. 13, p. xi + 1–230, pls. 1–4.Google Scholar
Henningsmoen, G. 1951. Remarks on the classification of trilobites. Norsk Geologisk Tidsskrift, 29:174217.Google Scholar
International Code Of Zoological Nomenclature. 1999. Fourth edition, The International Trust for Zoological Nomenclature, Natural History Museum, London, pp. xxix + 1–306.Google Scholar
Jell, P. A. 2003. Phylogeny of early Cambrian trilobites. Special papers in palaeontology, 70:4557.Google Scholar
Jell, P. A. and Adrain, J. M. 2003. Available generic names for trilobites. Memoirs of the Queensland Museum, 48(2):331551.Google Scholar
Kaesler, R. L. (ED.). 1997. Treatise on Invertebrate Paleontology, Pt. O., Arthropoda 1, Trilobita, 1 (revised). Geological Society of America and University of Kansas Press, Lawrence, 530 p.Google Scholar
Kobayashi, T. 1935. The Cambro-Ordovician Formations and Faunas of South Chosen. Palaeontology, Pt. 3, Cambrian Faunas of South Chosen. Journal of the Faculty of Science, Imperial University of Tokyo, Section 2, Geology, Mineralogy, Geography, Seismology, vol. 4(2):49344, pls. 1–24.Google Scholar
Mcnamara, K. J. 1986. The role of heterochrony in the evolution of Cambrian trilobites. Biological Reviews, vol. 61:121156.CrossRefGoogle Scholar
Miquel, J. 1905. Essai sur le Cambrien de la Montagne Noire, Coulouma, L'Acadien. Bulletin Societé Géologique de France, Series 4, vol. 5, p. 465483, pl. 15.Google Scholar
Moore, R. C. (Ed.). 1959. Treatise on invertebrate paleontology, Pt. O, Arthropoda 1. Geological Society of America and University of Kansas Press. Boulder and Lawrence. 560 p.Google Scholar
Öpik, A. A. 1967. The Mindyallan Fauna of north-western Queensland. Commonwealth of Australia, Bureau of Mineral Resources, Geology and Geophysics. Bulletin 74, vol. 1: text, xvi + 1–404; vol. 2: appendixes, plates and index, v + 1–166.Google Scholar
Öpik, A. A. 1982. Dolichometopid trilobites of Queensland, Northern Territory, and New South Wales. Commonwealth of Australia, Bureau of Mineral Resources, Geology and Geophysics. Bulletin 175, pv + 1–85, 32 pls.Google Scholar
Palmer, A. R. 1968. Cambrian trilobites of east-central Alaska. United States Geological Survey Professional Paper 559–B: 1115.CrossRefGoogle Scholar
Peng, S., Babcock, L. E., and Lin, H. 2004. Polymerid trilobites from the Cambrian of northwestern Hunan, China. Volume 1. Corynexochida. Lichida and Asaphida, viii + 1–332 p., pls. 1–63, Science Press, Beijing.Google Scholar
Rasetti, F. 1945. Faunes Cambriennes des conglomérates de la “Formation de Sillery.” Naturaliste Canadien, 72:5367.Google Scholar
Rasetti, F. 1948. Middle Cambrian trilobites from the conglomerates of Quebec. Journal of Paleontology, 22:315339.Google Scholar
Rasetti, F. 1951. Middle Cambrian stratigraphy and faunas of the Canadian Rocky Mountains. Smithsonian Miscellaneous Collections 116,1277.Google Scholar
Rasetti, F. 1952. Ventral cephalic sutures in Cambrian trilobites. American Journal of Science, 250:885898.CrossRefGoogle Scholar
Rasetti, F. 1963. Middle Cambrian ptychoparioid trilobites from the conglomerates of Quebec. Journal of Paleontology, 37:575594.Google Scholar
Rudolph, F. 1994. Die Trilobiten der mittelkambrisehen Geschiebe; Systematik, Morphologie und ökologie. (Verlag Frank Rudolph), Wankendorf. 1309.Google Scholar
Swinnerton, H. H. 1915. Suggestions for a revised classification of trilobites. Geological Magazine, new series 2:407496 and 538–545.Google Scholar
Suvorova, N. P. 1964. Corynexochoid trilobites and their historical development. Trudy Palaeontologischeskogo Instituta Academiya Nauk SSR, vol. 103, p.1319.Google Scholar
Walcott, C. D. 1889. Description of new genera and species of fossils from the Middle Cambrian. Proceedings of the United States National Museum, 11:441446.CrossRefGoogle Scholar
Walcott, C. D. 1908. Cambrian trilobites. Smithsonian Miscellaneous Collections, 53:1352.Google Scholar
Walcott, C. D. 1916. Cambrian Geology and Paleontology, III (5), Cambrian trilobites. Smithsonian Miscellaneous Collections, 64(5):303456, index.Google Scholar
Westergård, A. H. 1948. Non-agnostidean trilobites of the Middle Cambrian of Sweden. Sveriges Geologiska Undersøkning, Series C, no. 498:132.Google Scholar
Whitehouse, F. W. 1939. The Cambrian faunas of northeastern Australia, Pt. 3, the polymerid trilobites (with Supplement no. 1). Memoir of the Queensland Museum, 11:179282.Google Scholar
Whittington, H. B. 1988. Hypostomes and ventral cephalic sutures in Cambrian trilobites. Palaeontology, 31:577609.Google Scholar
Whittington, H. B. 2007a. Reflections on the classification of the Trilobita. New York State Museum Bulletin, 507:225230.Google Scholar
Whittington, H. B. 2007b. Theodenisia and Peracheilus: enigmatic trilobites from Laurentia. Journal of Paleontology, 81:11391145.CrossRefGoogle Scholar