Hostname: page-component-848d4c4894-nr4z6 Total loading time: 0 Render date: 2024-06-02T17:05:29.626Z Has data issue: false hasContentIssue false

Early Silurian (Llandovery) encrinurine trilobites from the Mackenzie Mountains, Canada

Published online by Cambridge University Press:  20 May 2016

Gregory D. Edgecombe
Affiliation:
Department of Invertebrates, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024, Department of Geological Sciences, Columbia University, New York, New York 10027 and
Brian D. E. Chatterton
Affiliation:
Department of Geology, University of Alberta, Edmonton, Canada T6G 2E3

Abstract

Llandovery Encrinurinae from the Whittaker Formation in the central Mackenzie Mountains include Cromus canorus n. sp., Distyrax cooperi n. sp., Distyrax n. sp. A, Perryus bartletti n. sp., and Encrinurus n. sp. Additional diversity of Distyrax Lane, 1988, demands a revised generic diagnosis with emphasis on pygidial homologies; new species are described from the Llandovery of Newfoundland and Ontario. Several characters suggest a sister group relationship between Distyrax and Encrinurus s.s. A lectotype is designated for the Llandovery species Encrinurus elegantulus Billings, 1866. Cromus canorus n. sp. is closely allied to other northern Laurentian Llandovery species. Synapomorphies of Cromus are inclusive for Encrinuraspis as revised by Snajdr, 1985. The long stratigraphic range and morphological conservatism of Cromus are correlated with occurrence in distal mudstone facies. Ontogenetic material for Distyrax n. sp. A, Cromus canorus, and Perryus bartletti is described, with consideration of librigenal spine homologies in Encrinurinae. Humaencrinuroides Nan, 1985, is a pliomerid of the new subfamily Quinquecostinae, and not a subgenus of Encrinuroides Reed.

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

Angelin, N. P. 1854. Palaeontologia Scandinavica. I: Crustacea formationis transitionis, Fascicule 2:2192.Google Scholar
Baillie, P. W., Banks, M. R., and Rickards, R. B. 1978. Early Silurian graptolites from Tasmania and their significance. Search, 9:4647.Google Scholar
Barrande, J. 1846. Notice préliminaire sur le Silurien et les Trilobites de Bohême. C. L. Hirschfeld, Leipzig, 97 p.Google Scholar
Barrande, J. 1852. Systême Silurien de centre de la Bohême. Ière partie. Rechérches paléontologiques, I: Crustacés, Trilobites. Prague, Paris, 935 p.Google Scholar
Billings, E. 1866. Catalogues of the Silurian fossils of the Island of Anticosti, with descriptions of some new genera and species. Geological Survey of Canada, Separate Report, 427:193.Google Scholar
Bolton, T. E. 1972. Geological map and notes on the Ordovician and Silurian litho- and biostratigraphy, Anticosti Island, Quebec. Geological Survey of Canada, Paper 71-19, 45 p.Google Scholar
Bolton, T. E. 1981. Ordovician and Silurian biostratigraphy, Anticosti Island, Québec, p. 4159. In Lesperance, P. J. (ed.), IUGS, Subcommission on Silurian Stratigraphy, Ordovician–Silurian Boundary Working Group, Field Meeting, Anticosti–Gaspé, Québec, 1981, II: Stratigraphy and Paleontology. Montréal.Google Scholar
Bolton, T. E., and Copeland, M. J. 1972. Paleozoic formations and Silurian biostratigraphy, Lake Timiskaming region, Ontario and Quebec. Geological Survey of Canada, Paper 72-15, 49 p.CrossRefGoogle Scholar
Chapman, F. 1912. New or little-known Victorian fossils in the National Museum. Part 14. On some Silurian trilobites. Proceedings of the Royal Society of Victoria, 24:293300.Google Scholar
Chatterton, B. D. E., and Perry, D. G. 1983. Silicified Silurian odontopleurid trilobites from the Mackenzie Mountains. Palaeontographica Canadiana, 1, 126 p.Google Scholar
Chatterton, B. D. E., and Perry, D. G. 1984. Silurian cheirurid trilobites from the Mackenzie Mountains northwestern Canada. Palaeontographica A, 184:178.Google Scholar
Chatterton, B. D. E., Edgecombe, G. D., and Tuffnell, P. A. 1990. Extinction and migration in Silurian trilobites and conodonts of northwestern Canada. Journal of the Geological Society, London, 147:703715.Google Scholar
Chlupáč, I. 1971. The youngest representative of the trilobite genus Cromus from the Silurian of Czechoslovakia. Věstnik Ústředniho ústavu geologickeho, 46:285288.Google Scholar
Chlupáč, I. 1987. Ecostratigraphy of Silurian trilobite assemblages of the Barrandian area, Czechoslovakia. Newsletters in Stratigraphy, 17:169186.Google Scholar
Churkin, M. 1961. Silurian trilobites from the Klamath Mountains, California. Journal of Paleontology, 35:168175.Google Scholar
Conway Morris, S. 1989. The persistence of Burgess Shale-type faunas: implications for the evolution of deeper-water faunas. Transactions of the Royal Society of Edinburgh: Earth Sciences, 80:271283.Google Scholar
De Mott, L. L. 1987. Platteville and Decorah trilobites from Illinois and Wisconsin, p. 6398. In Sloan, R. E. (ed.), Middle and Late Ordovician Lithostratigraphy and Biostratigraphy of the Upper Mississippi Valley. Minnesota Geological Survey, Report of Investigations, 35.Google Scholar
Douglas, R. J., and Norris, D. K. 1961. Camsell Bend and Root River map-areas. Geological Survey of Canada, Paper 61-13, 36 p.Google Scholar
Edgecombe, G. D., and Chatterton, B. D. E. 1987. Heterochrony in the Silurian radiation of encrinurine trilobites. Lethaia, 20:337351.Google Scholar
Edgecombe, G. D., and Chatterton, B. D. E. 1990a. Systematics of Encrinuroides and Curriella, with a new Early Silurian encrinurine from the Mackenzie Mountains. Canadian Journal of Earth Sciences, 27:820833.Google Scholar
Edgecombe, G. D., and Chatterton, B. D. E. 1990b. Mackenziurus, a new genus of the Silurian “Encrinurusvariolaris plexus (Trilobita). American Museum Novitates, 2968, 22 p.Google Scholar
Edgecombe, G. D., Speyer, S. E., and Chatterton, B. D. E. 1988. Protaspid larvae and phylogenetics of encrinurid trilobites. Journal of Paleontology, 62:779799.Google Scholar
Eldredge, N. 1979. Alternative approaches to evolutionary theory, p. 719. In Schwartz, J. H. and Rollins, H. B. (eds.), Models and Methodologies in Evolutionary Theory. Bulletin of the Carnegie Museum of Natural History, 13.Google Scholar
Emmrich, H. F. 1844. Zur Naturgeschichte der Trilobiten. Meinengen, 28 p.Google Scholar
Evitt, W. R., and Tripp, R. P. 1977. Silicified Middle Ordovician trilobites from the families Encrinuridae and Staurocephalidae. Palaeontographica (A), 157:109174.Google Scholar
Farris, J. S. 1988. Hennig86 reference, version 1.5. Port Jefferson Station, New York, 15 p.Google Scholar
Farris, J. S., Kluge, A. G., and Mickevich, M. R. 1982. Phylogenetic analysis, the monothetic group method, and myobatrachid frogs. Systematic Zoology, 31:317327.Google Scholar
Fortey, R. A. 1979. Early Ordovician trilobites from the Catoche Formation (St. George Group), western Newfoundland. Geological Survey of Canada Bulletin, 321:61114.Google Scholar
Fortey, R. A. 1980a. Generic longevity in Lower Ordovician trilobites: relation to environment. Paleobiology, 6:2431.Google Scholar
Fortey, R. A. 1980b. The Ordovician trilobites of Spitsbergen. III. Remaining trilobites of the Valhallfonna Formation. Norsk Polarinstitutt Skrifter, 171, 163 p.Google Scholar
Frech, F. 1888. Über das Devon der Ostalpen, nebst Bemerkungen über das Silur und einem palaontologischen Alpen. Zeitschrift für Deutschen geologischen Gesellschaft, Jahrgang 1887:659737.Google Scholar
Gaertner, H.-R. von. 1930. Silurische und tiefuntdevonische Trilobiten und Brachiopoden aus den Zentralkarnischen Alpen. Preussische geologische Landesanstalt Jahrbuch, 51:188252.Google Scholar
Gass, K. C., and Mikulic, D. G. 1982. Observations on the Attawapiskat Formation (Silurian) trilobites of Ontario with description of a new encrinurine. Canadian Journal of Earth Sciences, 19:589596.Google Scholar
Gass, K. C., Edgecombe, G. D., Ramsköld, L., Mikulic, D. G., and Watkins, R. 1992. Silurian Encrinurinae (Trilobita) from the central United States. Journal of Paleontology, 66:7589.Google Scholar
Hall, J. 1852. Paleontology of New York. Volume 2. C. van Benthuysen, Albany, 362 p.Google Scholar
Hall, J. 1867. Account of some new or little known species of fossils from rocks of the age of the Niagara Group. Report of the New York State Cabinet of Natural History, 20:305401.Google Scholar
Hall, J., and Whitfield, R. P. 1875. Descriptions of invertebrate fossils, mainly from the Silurian System. Report of the Geological Survey of Ohio, Volume 2, Geology and Paleontology, Part 2, Paleontology:65161.Google Scholar
Holloway, D. J., and Neal, J. V. 1982. Trilobites from the Mount Ida Formation (Late Silurian-Early Devonian), Victoria. Proceedings of the Royal Society of Victoria, 94:133154.Google Scholar
Howells, Y. 1982. Scottish Silurian trilobites. Palaeontographical Society Monograph, 135:176.Google Scholar
Jell, P. A. 1985. Tremadoc trilobites of the Digger Island Formation, Waratah Bay, Victoria. Memoirs of the Museum of Victoria, 46:5388.Google Scholar
Lane, P. D. 1984. Silurian trilobites from Hall Land and Nyeboe Land, western North Greenland. Rapport Gr⊘nlands geologiske Unders⊘gelse, 121:5375.Google Scholar
Lane, P. D. 1988. Silurian trilobites from Peary Land, central North Greenland. Rapport Gr⊘nlands geologiske Unders⊘gelse, 137:93117.Google Scholar
Ludvigsen, R., and Tripp, R. P. 1990. Silurian trilobites from the northern Yukon Territory. Royal Ontario Museum, Life Sciences Contributions, 153, 59 p.Google Scholar
Maksimova, Z. A. 1962. Trilobity ordovika i silura sibirskoy platformy. Trudy Vsesoiuznyi nauchno-issledovatel'skii geologicheskii institut [VSEGEI], 76:1214.Google Scholar
Männil, R. M. 1958. Trilobity semeystv Cheiruridae i Encrinuridae iz Estonii. Eesti NSV Teaduste Akadeemia Geoloogia Instituudi Uurimused, 3:165212.Google Scholar
Männil, R. 1968. Encrinurus schmidti sp. n. (Trilobita) iz Llandoveri Estonii. Eesti NSV Teaduste Akadeemia Toimetised Keemia Geoloogia, 17:273278.Google Scholar
Männil, R. 1978. Trilobity vidovoy gruppy Encrinurus punctatus v Wenloke Pribaltiki. Eesti NSV Teaduste Akadeemia Toimetised Keemia Geoloogia, 27:198–115.Google Scholar
Miller, S. A. 1880. Description of two new species from the Niagara Group and five from the Keokuk Group. Journal of the Cincinnati Society of Natural History, 2:254259.Google Scholar
Nan, R.-S. 1985. Upper Ordovician trilobites from the Walongtun Formation of eastern Yilehuli Shan Heilo Ngjiang Province. Bulletin of the Shenyang Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences, 12:5667.Google Scholar
Norford, B. S. 1981. The trilobite fauna of the Silurian Attawapiskat Formation, northern Ontario and northern Manitoba. Geological Survey of Canada, Bulletin 327, 37 p.Google Scholar
Northrop, S. A. 1939. Paleontology and stratigraphy of the Silurian rocks of the Port Daniel–Black Cape region, Gaspé. Geological Society of America Special Paper 21, 302 p.Google Scholar
Over, D. J., and Chatterton, B. D. E. 1987. Silurian conodonts from the southern Mackenzie Mountains, Northwest Territories, Canada. Geologica et Palaeontologica, 21:149.Google Scholar
Pek, I., and Vaněk, J. 1989. Index of Bohemian trilobites. Krajske vlastivedne muzeum Olomouc, 68 p.Google Scholar
Poulsen, C. 1934. The Silurian faunas of North Greenland. I. The fauna of the Cape Schuchert Formation. Meddelelser om Gr⊘nland, 72:146.Google Scholar
Přibyl, A., Vaněk, J., and Pek, I. 1985. Phylogeny and taxonomy of family Cheiruridae (Trilobita). Acta Universitatis Palackianae Olomucensis, Facultas Rerum Naturalium, Geographica–Geologica, 83:107197.Google Scholar
Raasch, G. O., Norford, B. S., and Wilson, D. W. R. 1961. The Silurian Aulacopleura Socialis in the Yukon Territory, p. 466480. In Raasch, G. O. (ed.), Geology of the Arctic, Volume 1. University of Toronto Press, Toronto.Google Scholar
Ramsköld, L. 1986. Silurian encrinurid trilobites from Gotland and Dalarna, Sweden. Palaeontology, 29:527575.Google Scholar
Raymond, P. E. 1913. Trilobita, p. 692729. In von Zittel, K. A. R. and Eastman, C. R. (eds.), Text-Book of Paleontology. Volume 1. Macmillan, London.Google Scholar
Reed, F. R. C. 1931. The lower Paleozoic trilobites of the Girvan district, Ayrshire. Supplement 2. Palaeontographical Society Monograph:130.Google Scholar
Rosenstein, E. 1941. Die Encrinurus—Arten des Estlandischen Silurs. Annales Societatis rebus naturae investigandis in Universitate tartuensis constitutae, 47:4977.Google Scholar
Salter, J. W. 1853. Figures and Descriptions Illustrative of British Organic Remains, Number 2. Memoir of the Geological Survey of Great Britain, 78 p.Google Scholar
Schrank, E. 1977. Zur paläobiogeographie silurischer Trilobiten. Neues Jahrbuch fur Geologie und Paläontologie, Abhandlungen 155:108136.Google Scholar
Shrock, R. R., and Twenhofel, W. H. 1939. Silurian fossils from northern Newfoundland. Journal of Paleontology, 13:241266.Google Scholar
Šnajdr, M. 1983. New Silurian trilobites from Bohemia. Věstnik Ústředniho ústavu geologickeho, 58:175178.Google Scholar
Šnajdr, M. 1985. Bohemian representatives of the subfamily Encrinurinae (Trilobita). Sbornik Geologickych Věd, Paleontologie, 27:946.Google Scholar
Strusz, D. L. 1980. The Encrinuridae and related trilobite families, with a description of Silurian species from southeastern Australia. Palaeontographica A, 168:168.Google Scholar
Talent, J. A. 1965. The Silurian and early Devonian faunas of the Heathcote district, Victoria. Memoirs of the Geological Survey of Victoria, 26(1964):155.Google Scholar
Temple, J. T., and Wu, H.-J. 1990. Numerical taxonomy of Encrinurinae (Trilobita): additional species from China and elsewhere. Transactions of the Royal Society of Edinburgh, Earth Sciences, 81:209219.Google Scholar
Törnquist, S. L. 1884. Undersökningar öfver Siljansområdets trilobitfauna. Sveriges Geologiska Undersökning, C66:1101.Google Scholar
Tripp, R. P. 1962. The Silurian trilobite Encrinurus punctatus (Wahlenberg) and allied species. Palaeontology, 5:460477.Google Scholar
Tripp, R. P. 1965. Trilobites from the Albany Division (Ordovician) of the Girvan district, Ayrshire. Palaeontology, 8:577603.Google Scholar
Twenhofel, W. H. 1928. Geology of Anticosti Island. Geological Survey of Canada, Memoir 154, 481 p.Google Scholar
Twenhofel, W. H., and Shrock, R. R. 1937. Silurian strata of Notre Dame Bay and Exploits Valley, Newfoundland. Geological Society of America Bulletin, 48:17431772.Google Scholar
Vogdes, A. W. 1886. Description of a new crustacean from the Clinton Group of Georgia, with remarks upon others. New York, 5 p.Google Scholar
Vogdes, A. W. 1890. A bibliography of Paleozoic Crustacea from 1698 to 1889, including a list of North American species and a systematic arrangement of genera. U.S. Geological Survey Bulletin 63, 177 p.Google Scholar
Wahlenberg, G. 1818. Petrificata Telluris Svecanae. Nova Acta Regiae Societatis Scientiatum Upsaliensis, 8:1116.Google Scholar
Webby, B. D. 1974. Upper Ordovician trilobites from central New South Wales. Palaeontology, 17:203252.Google Scholar
Webby, B. D., Moors, H. T., and McLean, R. A. 1970. Malongullia and Encrinuraspis, new Ordovician trilobites from New South Wales, Australia. Journal of Paleontology, 44:881887.Google Scholar
Whittington, H. B., and Campbell, K. S. W. 1967. Silicified Silurian trilobites from Maine. Bulletin of the Museum of Comparative Zoology at Harvard College, 135:447483.Google Scholar
Zhang, W.-T. 1983. On the subfamily Coronocephalinae (Trilobita). Palaeontologia Cathayana, 1:195257.Google Scholar