Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-26T07:21:34.904Z Has data issue: false hasContentIssue false

The only known cyclopygid–‘atheloptic’ trilobite fauna from North America: the upper Ordovician fauna of the Pyle Mountain Argillite and its palaeoenvironmental significance

Published online by Cambridge University Press:  27 March 2012

ALAN W. OWEN*
Affiliation:
School of Geographical and Earth Sciences, University of Glasgow, Gregory Building, Lilybank Gardens, Glasgow G12 8QQ, Scotland, UK
DAVID L. BRUTON
Affiliation:
The Natural History Museum (Geology), University of Oslo, Postboks 1172 Blindern, N-0318, Oslo, Norway
*
Author for correspondence: [email protected]

Abstract

The trilobite fauna of the upper Ordovician (middle Katian) Pyle Mountain Argillite comprises a mixture of abundant mesopelagic cyclopygids and other pelagic taxa and a benthic fauna dominated by trilobites lacking eyes. Such faunas were widespread in deep water environments around Gondwana and terranes derived from that continent throughout Ordovician time but this is the only known record of such a fauna from North America and thus from Laurentia. It probably reflects a major sea level rise (the ‘Linearis drowning events’) as does the development of coeval cyclopygid-dominated deep water trilobite faunas in terranes that were marginal to Laurentia and are now preserved in Ireland and Scotland. The Pyle Mountain Argillite trilobite fauna occurs with a deep water Foliomena brachiopod fauna and comprises 22 species. Pelagic trilobites (mostly cyclopygids) constitute 36% of the preserved sclerites, and 45% of the fauna is the remains of trilobites lacking eyes, including one new species, Dindymene whittingtoni sp. nov. Three species of cyclopygid are present, belonging in Cyclopyge, Symphysops and Microparia (Heterocyclopyge). Cyclopygids are widely thought to have been stratified in the water column in life and thus their taxonomic diversity reflects the relative depths of the sea-beds on which their remains accumulated. A tabulation of middle and upper Katian cyclopygid-bearing faunas from several palaeoplates and terranes arranged on the basis of increasing numbers of cyclopygid genera allows an assessment of the relative depth ranges of the associated benthic taxa. The Pyle Mountain Argillite fauna lies towards the deeper end of this depth spectrum.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2012

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

References

Adrain, J. M., Edgecombe, G. D., Fortey, R. A., Laurie, J., McCormick, T., Owen, A. W., Waisfeld, B., Webby, B. D., Westrop, S. R. & Zhou, J.-Y. 2004. Trilobites. In The Great Ordovician Biodiversification Event (eds Webby, B. D., Droser, M. L. & Paris, F.), pp. 231–54. New York: Columbia University Press.CrossRefGoogle Scholar
Angelin, N. P. 1854. Palaeontologia Scandinavica. Fasc. 2. pp. i–ix, 2192, pls. 25–41 Holmiae: Academiae Regiae Scientarum Suecanae.Google Scholar
Apollonov, M. K. 1974. Ashgill trilobites from Kazakhstan. Alma Ata: Akademiya Nauk Kazakh SSR, pp. 1136, pls. 1–21.Google Scholar
Bancroft, B. B. 1949. Upper Ordovician trilobites of zonal value in south-east Shropshire (ed. A. Lamont). Proceedings of the Royal Society of London (B) 136, 291315.Google Scholar
Barrande, J. 1846. Notice préliminaire sur le Système Silurien et les Trilobites de Bohême. Hirschfeld, Leipzig, vi+191.Google Scholar
Barrande, J. 1847. Über das Hypostoma und Epistoma, zwei analoge, aber verschiedene Organe der Trilobiten. Neues Jahrbuch für Mineralogie, Geologie und Paläontologie Jahrgang 1847, 385–99.Google Scholar
Barrande, J. 1852. Système Silurien du Centre de la Bohême. I. Recherches Paléontologiques, 1 (Crustacés: Trilobites). Prague & Paris. xxx+ 935 pp.Google Scholar
Barrande, J. 1872. Système Silurien du Centre de la Bohême, I. Recherches Paléontologiques I. Supplement (Trilobites Crustacés divers et Poissons). Prague & Paris. 647 pp.Google Scholar
Bartholomew, M. J. & Tillman, C. G. 1977. Microparia, a cyclopygid trilobite of Porterfield age from Virginia. Journal of Paleontology 51, 131–5.Google Scholar
Bergström, J. 1973. Palaeoecologic aspects of an Ordovician Tretaspis fauna. Acta Geologica Polonica 23, 179206.Google Scholar
Bergström, S. M., Chen, X., Gutiérrez-Marco, J. C. & Dronov, A. 2009. The new chronostratigraphic classification of the Ordovician System and its relations to major regional series and stages and to δ13C chemostratigraphy. Lethaia 42, 97107.Google Scholar
Beyrich, E. 1845. Ueber einige böhmische Trilobiten. Berlin, 47 pp.Google Scholar
Boucot, A. J., Field, M. T., Fletcher, R., Forbes, W. H., Naylor, R. S. & Pavlides, L. 1964. Reconnaissance bedrock geology of the Presque Isle Quadrangle, Maine. Quadrangle Mapping Series No. 2, Department of Economic Development, Maine Geological Survey, Augusta Maine, pp. 1123, + map scale 1:62.500.Google Scholar
Brøgger, W.C. 1886. Ueber die Ausbildung des hypostomes bei einigen skandinavischen Asaphiden. Bihang till Kongliga Svenska Vetenskaps-Akademiens Handlingar 11 (3), 178, pls 1–3.Google Scholar
Bruton, D. L. 1968. The trilobite genus Panderia from the Ordovician of Scandinavia and the Baltic areas. Norsk Geologisk Tidsskrift 48, 153.Google Scholar
Bruton, D. L. & Høyberget, M. 2006. A reconstruction of Telephina bicuspis, a pelagic trilobite from the Middle Ordovician of the Oslo Region, Norway. Lethaia 39, 359–64.CrossRefGoogle Scholar
Budil, P., Fatka, O., Kolár, P. & David, M. 2011. Preliminary report on Arthrorhachis Hawle and Corda, 1847 (Agnostida) in the Prague Basin (Barrandian area, Czech Republic). In Ordovician of the World (eds Gutiérrez-Marco, J. C., Rábano, I & García-Bellido, D.), pp. 65–8. Cuadernos del Museo Geolominero, 14. Madrid: Instituto Geológico y Minero de España.Google Scholar
Candela, Y. 2006. Late Ordovician brachiopod faunas from Pomeroy, Northern Ireland: a palaeoenvironmental synthesis. Transactions of the Royal Society of Edinburgh: Earth Sciences 96 (for 2005), 317–25.Google Scholar
Cocks, L. R. M. & Fortey, R. A. 1990. Biogeography of Ordovician and Silurian faunas. In Palaeozoic Palaeogeography and Biogeography (eds McKerrow, W. S. & Scotese, C. R.), pp. 97104. Geological Society of London Memoir no. 12.Google Scholar
Cocks, L. R. M. & Rong, J.-Y. 1988. A review of the late Ordovician Foliomena brachiopod fauna. Palaeontology 31, 5367.Google Scholar
Cooper, B. N. 1953. Trilobites from the Lower Champlainian formations of the Appalachian Valley. Memoir of the Geological Society of America 55, 169.Google Scholar
Cooper, J. A. & Kindle, C. H. 1936. New brachiopods and trilobites from the Upper Ordovician of Percé, Quebec. Journal of Paleontology 10, 348–72.Google Scholar
Dalman, J. W. 1827. Om Palaeaderna eller de så kallade Trilobiterna. Kongliga Svenska Vetenskaps-Akademiens Handlingar 1826 (2), 113–62, 226–94, pls 1–6.Google Scholar
Dean, W. T. 1963. The Ordovician faunas of South Shropshire, 3. Bulletin of the British Museum (Natural History), Geology 7, 213–54.Google Scholar
Dean, W. T. 1971. The trilobites of the Chair of Kildare Limestone (Upper Ordovician) of eastern Ireland, Part 1. Monograph of the Palaeontographical Society 125 (531), 160, pls 1–25.Google Scholar
Dean, W. T. 1974. The trilobites of the Chair of Kildare Limestone (Upper Ordovician) of eastern Ireland. Part 2. Monograph of the Palaeontographical Society 128 (539), 6198, pls 26–44.Google Scholar
Fortey, R. A. 1975. The Ordovician trilobites of Spitsbergen II. Asaphidae, Nileidae, Raphiophoridae and Telephinidae of the Valhallfonna Formation. Skrifter Norsk Polarsinstitutt 162, 1207.Google Scholar
Fortey, R. A. 1984. Global earlier Ordovician transgressions and regressions and their biological implications. In Aspects of the Ordovician System (ed. Bruton, D. L.), pp. 3750. Oslo: Universitetsforlaget.Google Scholar
Fortey, R. A. 1980. The Ordovician trilobites of Spitsbergen. III. Remaining trilobites of the Valhallfonna Formation. Skrifter Norsk Polarinstitutt 171, 1113, pls 1–25.Google Scholar
Fortey, R. A. 1985. Pelagic trilobites as an example of deducing life habits of extinct arthropods. Transactions of the Royal Society of Edinburgh: Earth Sciences 76, 219–30.Google Scholar
Fortey, R. A. 1997. Late Ordovician trilobites from southern Thailand. Palaeontology 40, 397449.Google Scholar
Fortey, R. A. & Cocks, L. R. M. 2003. Palaeontological evidence bearing on global Ordovician-Silurian continental reconstructions. Earth-Science Reviews 61, 245307.Google Scholar
Fortey, R. A., Harper, D. A. T., Ingham, J. K., Owen, A. W., Parkes, M. A., Rushton, A. W. A. & Woodcock, N. H. 2000. A revised correlation of Ordovician rocks in the British Isles. Geological Society Special Report 24, 183.Google Scholar
Fortey, R. A. & Owens, R. M. 1987. The Arenig Series in South Wales. Bulletin of the British Museum Natural History (Geology) 41, 69307.Google Scholar
Fortey, R. A. & Owens, R. M. 1999. Feeding habits in trilobites. Palaeontology 42, 429–65.Google Scholar
Ghobadi Pour, M., McCobb, L. M. E., Owens, R. M. & Popov, L. E. 2011. Late Ordovician trilobites from the Karagach Formation of the western Tarbagati Range, Kazakhstan. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 101 (for 2010), 161–87Google Scholar
Gürich, G. 1907. Versuch einer Neueinteilung der Trilobiten. Zentralblatt für Mineralogie, Geologie und Paläontologie 1907, 129–33.Google Scholar
Hammann, W. 1992. The Ordovician trilobites from the Iberian Chains in the province of Aragon, NE-Spain 1. The trilobites of the Cystoid Limestone (Ashgill Series). Beringeria 6, 1219.Google Scholar
Hammann, W. & Leone, F. 1997. Trilobites of the post-Sardic (Upper Ordovician) sequence of southern Sardinia. Part 1. Beringeria 20, 1217.Google Scholar
Hammann, W. & Leone, F. 2007. Trilobites from the post-Sardic (Upper Ordovician) sequence of southern Sardinia. Part 2. Beringeria 38, 3138.Google Scholar
Hansen, T. 2009. Trilobites of the Middle Ordovician Elnes Formation of the Oslo Region, Norway. Fossils and Strata 56, 1215.Google Scholar
Haq, B. U. & Schutter, S. R. 2008. A chronology of Paleozoic sea-level changes. Science 322, 64–8.Google Scholar
Harper, D. A. T. & Stewart, S. 2008. Brachiopod biofacies in the Barr and Ardmillan groups, Girvan: Ordovician biodiversity trends on the edge of Laurentia. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 98 (for 2007), 281–9.Google Scholar
Hawle, I. & Corda, A. J. C. 1847. Prodrom einer Monographie der böhmischen Trilobiten. Prague: Calve, 1176.Google Scholar
Hoel, O. A. 1999. Trilobites of the Hagastrand Member (Tøyen Formation, lowermost Arenig) from the Oslo Region, Norway. Part II. Remaining non-asaphid groups. Norsk Geologisk Tidsskrift 79, 259–80.Google Scholar
Hörbinger, F. & Vanĕk, J. 1985. New cyclopygid trilobites from the Ordovician of Bohemia. Časopsis pro Mineralogii a Geologii 30, 5964.Google Scholar
Horný, R. & Bastl, F. 1970. Type specimens of fossils in the National Museum, Prague, Volume 1, Trilobita. Prague: National Museum, 354 pp., 20 pls.Google Scholar
Hughes, C. P., Ingham, J. K. & Addison, R. 1975. The morphology, classification and evolution of the Trinucleidae (Trilobita). Philosophical Transactions of the Royal Society of London B. Biological Sciences 272, 537607.Google Scholar
Ingham, J. K. 1970. A monograph of the upper Ordovician trilobites from the Cautley and Dent districts of Westmorland and Yorkshire. 1. Monograph of the Palaeontographical Society 124 (526), 158.Google Scholar
Ingham, J. K. 1974. A monograph of the upper Ordovician trilobites from the Cautley and Dent districts of Westmorland and Yorkshire. 2. Monograph of the Palaeontographical Society 128 (538), 5987.Google Scholar
Ingham, J. K. 1977. A monograph of the upper Ordovician trilobites from the Cautley and Dent districts of Westmorland and Yorkshire. 2. Monograph of the Palaeontographical Society 130 (546), 89121, pls 19–27.Google Scholar
Ingham, J. K. In press. The Ordovician pelagic trilobite Ellipsotaphrus (Cyclopygoidea, Ellipsotaphridae) and its allies. Earth and Environmental Science Transactions of the Royal Society of Edinburgh.Google Scholar
Jaekel, O. 1909. Über die Agnostiden. Zeitschrift der Deutschen Geologischen Gesellschaft 61, 380401.Google Scholar
Jell, P. A. & Adrain, J. M. 2003. Available generic names for trilobites. Memoirs of the Queensland Museum 48, 331553.Google Scholar
Ji, Z.-L. 1986. Upper Ordovician (middle Caradoc–early Ashgill) trilobites from the Pagoda Formation in South China. Professional Papers in Palaeontology and Stratigraphy 15, 133, pls 1–6 (in Chinese).Google Scholar
Kaesler, R. L. (ed.) 1997. Treatise on Invertebrate Paleontology. Part O. Arthropoda 1, Trilobita (revised). Lawrence: Geological Society of America and University of Kansas Press.Google Scholar
Karim, T. S. 2009. Late Ordovician trilobites from northwest Iran and their biogeographical affinities. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 99 (for 2008), 101–24.Google Scholar
Kielan, Z. 1957. On the trilobite family Staurocephalidae. Acta Palaeontologica Polonica 2, 155–80.Google Scholar
Kielan, Z. 1960. Upper Ordovician trilobites from Poland and some related forms from Bohemia and Scandinavia. Palaeontologia Polonica 11 (for 1959), i–vi, 1198, pls 1–36.Google Scholar
Kielan-Jaworowska, Z., Bergström, J & Ahlberg, P. 1991. Cheirurina (Trilobita) from the Upper Ordovician of Västergötland and other regions of Sweden. Geologiska Föreningens i Stockholm Förhandlingar 113, 219–44.Google Scholar
Kolobova, I. M. 1972. New Late Ordovician trilobites from southeastern Kazakhstan. In Novye vidy drevnikh rastenii i bespozvonochnykh SSSR (ed. Zanina, I. E.), pp. 242–6. Moscow: Nauka (in Russian).Google Scholar
Kobaysahi, T. 1939. On the agnostids. Journal of the Faculty of Science, Tokyo University, Section 2 5, 66198.Google Scholar
Kozák, V. & Vaněk, J. 1997. Dindymene kenchrias n. sp. (Trilobita) in the Vinice Formation (Berounian Stage, Ordovician) of the Prague Basin, Czech Republic. Palaeontologia Bohemiae 3, 1012.Google Scholar
Krueger, H.-H. 1972. Nachiven der Trilobitengattung Raymondella in Geschieben. Geologie 21 (7), 856–8.Google Scholar
Kutorga, S. 1854. Einige Sphaerexochus und Cheirurus aus den silurischen Kalksteingeschichten des Gouvernements von St. Petersburg. Verhandlungen der Kaiserlichen mineralogischen Gesellschaft zu St. Petersburg 13, 105–26.Google Scholar
Lane, P. D. 1971. British Cheirurudae (Trilobita). Monograph of the Palaeontographical Society 125 (530), 195.Google Scholar
Lespérance, P. J. 1968. Ordovician and Silurian trilobite faunas of the White Head Formation, Percé Region, Québec. Journal of Paleontology 42, 811–26.Google Scholar
Lespérance, P. J., Malo, M., Sheehan, P. M. & Skidmore, W. B. 1987. A stratigraphical and faunal revision of the Ordovician-Silurian strata of the Percé area, Quebec. Canadian Journal of Earth Sciences 24, 117–34.CrossRefGoogle Scholar
Lespérance, P. J. & Sheehan, P. M. 1988. Trilobites et brachiopodes ashgilliens (Ordovicien supérieur) de l’ < Assise> de Fosse, Bande de Sambre-Meuse (Belgique). Bulletin de L'Institut Royal des Science Naturelles de Belgique, Sciences de la Terre 57 (for 1987), 91123.Google Scholar
Lespérance, P. J. & Weissenberger, J. A. W. 1998. Trilobites of the Pabos Formation (Ashgillian, Upper Ordovician), Percé area, Quebec. Journal of Paleontology 72, 303–16.Google Scholar
Linnarsson, J. G. O. 1869. Om Västergötlands Cambriska och Siluriska aflagringar. Kongliga Svenska Vetenskaps-Akademiens Handlingar 8, 189.Google Scholar
Lu, Y.-H. 1957 Trilobita. In Index fossils of China. Invertebrates (3) (eds Gu, Z.-W. et al.), pp. 249–94. Beijing Science Press (in Chinese).Google Scholar
Lu, Y.-H. 1962. Middle Ordovician index trilobites. In Handbook of the Index Fossils of the Yangtze Region (ed. Wang, Y.), pp. 52–3. Beijing: Science Press (in Chinese).Google Scholar
McCormick, T. & Fortey, R. A. 1998. Independent testing of a paleobiological hypothesis: the optical design of two Ordovician pelagic trilobites reveals their relative palaeobathymetry. Paleobiology 24, 235–53.Google Scholar
M'Coy, F. 1846. A Synopsis of the Silurian Fossils of Ireland. Dublin, 72 pp., 5 pls.Google Scholar
Månsson, K. 2000. Dionidid and raphiophorid trilobites from the middle Ordovician (Viruan Series) of Jämtland, central Sweden. Transactions of the Royal Society of Edinburgh: Earth Sciences 90 (for 1999), 317–29.Google Scholar
Marek, L. 1952. Contribution to the stratigraphy and faunas of the upper part of the Králův Dvůr Shales (Ashgillian). Sbornik Ústředního Ústavu Geologického 19, 429–55.Google Scholar
Marek, L. 1961. The trilobite family Cyclopygidae Raymond in the Ordovician of Bohemia. Rozpravy Ústředni ústav geologický 28, 184.Google Scholar
Morris, S. F. 1988. A review of British trilobites including a synoptic revision of Salter's monograph. Monograph of the Palaeontographical Society 140 (574), 1316.Google Scholar
Neuman, R. B. 1994. Late Ordovician (Ashgill) Foliomena fauna brachiopods from northeastern Maine. Journal of Paleontology 68, 1218–34.CrossRefGoogle Scholar
Nicholson, H. A. & Etheridge, R. 1879. A monograph of the Silurian fossils of the Girvan district in Ayrshire with special reference to those in the “Gray Collection”, Vol. 1 (2). Edinburgh & London: William Blackwood and sons, pp. 137236.Google Scholar
Nicholson, H. A. & Etheridge, R. 1880. A monograph of the Silurian fossils of the Girvan district in Ayrshire with special reference to those in the “Gray Collection”, Vol. 3. Edinburgh & London: William Blackwood and sons, pp. 237341.Google Scholar
Nielsen, A. T. 1995. Trilobite systematics, biostratigraphy and palaeoecology of the Lower Ordovician Komstad Limestone and Huk Formations, southern Scandinavia. Fossils and Strata 38, 1374.Google Scholar
Nielsen, A. T. 1997. A review of Ordovician agnostid genera (Trilobita). Transactions of the Royal Society of Edinburgh: Earth Sciences 87 (for 1996), 463501.Google Scholar
Nielsen, A, T. 2004. Ordovician sea level changes: a Baltoscandian perspective. In The Great Ordovician Biodiversification Event (eds Webby, B. D., Droser, M. L. & Paris, F.), pp. 8495. New York: Columbia University Press.Google Scholar
Owen, A. W. 1981. The Ashgill trilobites of the Oslo Region, Norway. Palaeontographica Abt. A, 175, 188.Google Scholar
Owen, A. W. 1985. Trilobite abnormalities. Transactions of the Royal Society of Edinburgh: Earth Sciences 76, 255–72.Google Scholar
Owen, A. W. 1986. The uppermost Ordovician (Hirnantian) trilobites of Girvan, SW Scotland with a review of coeval trilobite faunas. Transactions of the Royal Society of Edinburgh: Earth Sciences 77, 231–9.CrossRefGoogle Scholar
Owen, A. W. & Bruton, D. L. 1980. Late Caradoc-early Ashgill trilobites of the central Oslo Region, Norway. Palaeontological Contributions from the University of Oslo 245, 163.Google Scholar
Owen, A. W. & Bruton, D. L. 2008. The environmental significance and fate of the trilobite fauna of the Pyle Mountain Argillite (Upper Ordovician), Maine. In Advances in Trilobite Research (eds Rabano, I., Gozalo, R. & Garcia-Bellido, D.), pp. 283–7. Cuadernos del Museo Geominero: Instituto Geologico y Minero de España, Madrid, 9.Google Scholar
Owen, A. W., Harper, D. A. T. & Rong, J.-Y. 1991. Hirnantian trilobites and brachiopods in space and time. In Advances in Ordovician Geology (eds Barnes, C. J. & Williams, S. H.), pp. 179–90. Geological Survey of Canada Paper 90–9.Google Scholar
Owen, A. W. & Ingham, J. K. 1996. Trilobites. In Fossils of the Upper Ordovician (eds Harper, D. A. T. & Owen, A. W.), pp. 138–73. Field Guide to Fossils 7. London: Palaeontological Association.Google Scholar
Owen, A. W. & Parkes, M. A. 2000. Trilobite faunas of the Duncannon Group: Caradoc stratigraphy, environments and palaeobiogeography of the Leinster terrane, Ireland. Palaeontology 43, 219–69.Google Scholar
Owen, A. W. & Romano, M. 2011. Deep shelf trilobite biofacies from the upper Katian (Upper Ordovician) of the Grangegeeth Terrane, eastern Ireland. Geological Journal 46, 416–26.Google Scholar
Owens, R. M. 2002. Cyclopygid trilobites from the Ordovician Builth-Llandrindod Inlier, central Wales. Palaeontology 45, 469–85.Google Scholar
Pålsson, C. 1996. Middle-Upper Ordovician trilobites and stratigraphy along the Kyrkbäcken rivulet in the Röstånga area, southern Sweden. GFF 118, 151–62.CrossRefGoogle Scholar
Parkes, M. A. & Harper, D. A. T. 1996. Ordovician brachiopod biogeography in the Iapetus suture zone of Ireland: provincial dynamics in a changing ocean. In Brachiopods (eds Copper, P. & Jin, J.), pp. 197202. Rotterdam: Balkema.Google Scholar
Pek, I. 1977. Agnostid trilobites of the Central Bohemian Ordovician. Sborník Geologických Věd, Paleontologie 19, 744.Google Scholar
Pek, I. & Prokop, R. J. 1984. New finds of the agnostid trilobites from the Ordovician of the Prague area (Czechoslovakia). Časopis Národního Muzea, Paleozoologie 153 (1), 1720.Google Scholar
Pollock, S. G., Harper, D. A. T. & Rhor, D. 1994. Late Ordovician nearshore faunas and depositional environments, northwestern Maine. Journal of Paleontology 68, 925–37.Google Scholar
Prantl, F. & Přibyl, A. 1947. Classification of some Bohemian Cheiruridae (Trilobitae). Sborník Národního Muzea v Praze 3B (1) 144.Google Scholar
Přibyl, A.. 1953. Seznam českých trilobitových rodu [Index of trilobite genera in Bohemia]. Ústredního Ústavu Geologického 25, 180.Google Scholar
Price, D. 1980. The Ordovician trilobite fauna of the Sholeshook Limestone Foramtion of South Wales. Palaeontology 23, 839–87.Google Scholar
Price, D. 1981. Ashgill trilobite faunas from the Llŷn Peninsula, North Wales. Geological Journal 16, 201–16.Google Scholar
Price, D. & Magor, P. M. 1984. The ecological significance of variation in generic composition of Rawtheyan (late Ordovician) trilobite faunas from North Wales, U.K. Geological Journal 19, 187200.Google Scholar
Raymond, P. E. 1925. Some trilobites of the lower Middle Ordovician of eastern North America. Bulletin of the Museum of Comparative Zoology, Harvard University 67, 1180.Google Scholar
Reed, F. R. C. 1897. Palaeontological appendix to Gardiner, C. I & Reynolds, S. H. An account of the Portraine Inlier (Co. Dublin). Quarterly Journal of the Geological Society of London 53, 520–39, pls 42, 43.Google Scholar
Reed, F. R. C. 1904. The Lower Palaeozoic trilobites of the Girvan district, Ayrshire. Monograph of the Palaeontographical Society 58 (276), 4996, pls 7–13.Google Scholar
Reed, F. R. C. 1914. The Lower Palaeozoic trilobites of Girvan. Supplement. Monograph of the Palaeontographical Society 67 (329), 156, pls 1–8.Google Scholar
Reed, F. R. C. 1935. The Lower Palaeozoic trilobites of Girvan. Supplement no. 3. Monograph of the Palaeontographical Society 88 (400), 164.Google Scholar
Repina, L. N., Yaskovich, B. V., Aksarina, N. A., Petrunina, Z. E., Poniklenko, I. A., Rubanov, D. A., Bogolova, G. V., Cheirullina, T. I. & Posochova, M. M. 1975. Stratigrafija I fauna niznegopaleozoja severnych predgorij Turkestanskogo i Alajskogo chrebtov (juznij Tjan’-Shan). Institut Geologii I Geofiziki 278, 1131, 48 pls. Novosibirsk: Akademija Nauk SSSR, Sibirskoe Otdelenie.Google Scholar
Rong, J.-Y., Zhan, R.-B. & Harper, D. A. T. 1999. Late Ordovician (Caradoc-Ashgill) brachiopod faunas with Foliomena based on data from China. Palaios 14, 412–31.Google Scholar
Ross, R. J. 1967. Calymenid and other Ordovician trilobites from Kentucky and Ohio. Professional Papers of the US Geological Survey 583 -B, 119.Google Scholar
Roy, D. C. 1987. Geologic map of the Caribou and northern Presque Isle quadrangles, Maine. Maine Geological Survey Open-File No. 87–2, 44 pp.Google Scholar
Roy, S. K. 1929. Contributions to palaeontology. Publications of the Field Museum of Natural History, Chicago (Geology) 4, 203–20, pls 32–40.Google Scholar
Rushton, A. W. A., Tunnicliff, S. P. & Tripp, R. P. 1996. The faunas of the Albany Group in the Girvan area and their palaeogeographical implications. Scottish Journal of Geology 32, 2332.Google Scholar
Salter, J. W. 1864. A monograph of the British trilobites from the Cambrian, Silurian and Devonian formations. Part 1. Monograph of the Palaeontographical Society 16, 180, pls 1–6.Google Scholar
Sars, M. 1835. Über einige neue oder unvollständig bekannte Trilobiten. Oken's Isis Jahrgang 1835, 333–43.Google Scholar
Schmidt, F. 1881. Revision der ostbaltischen Silurischen Trilobiten nebst geognostischer Übersicht der ostbaltischen Silurgebeits. Abteilung I. Phacopiden, Cheiruriden und Encrinuriden. Mémoires de l'Academie Impériale des Sciences de St-Pétersbourg (7) 30, (1), 1–237.Google Scholar
Schrank, E. 1972. Nileus-Arten (Trilobita) aus Geschieben des Tremadoc bis tieferen Caradoc. Berichte der deutschen Gesellschaft für geologische Wissenschaften, Reihe A, Geologie und Paläontologie 17, 351–75.Google Scholar
Schuchert, C. & Cooper, G. A. 1930. Upper Ordovician and Lower Devonian stratigraphy and Palaeontology of Percé, Quebec. American Journal of Science 20, 161–76, 265–88, 365–92.Google Scholar
Shaw, F. C. 1995. Ordovician trinucleid trilobites of the Prague Basin, Czech Republic. Paleontological Society Memoir 40, 123.Google Scholar
Shaw, F. C. 2000. Trilobites of the Králův Dvůr Formation (Ordovician) of the Prague Basin, Czech Republic. Věstnik Českého Geologického útavu 75 (4), 371404.Google Scholar
Sheehan, P. M. 1973. Brachiopods from the Jerrestad Mudstone (early Ashgillian) from a boring in Southern Sweden. Geologica et Palaeontologica 7, 5976.Google Scholar
Sheehan, P. M. & Lespérance, P. J. 1978. The occurrence of the Ordovician brachiopod Foliomena at Percé, Quebec. Canadian Journal of Earth Sciences 15, 454–58.Google Scholar
Shergold, J. H. & Laurie, J. R. 1997. Introduction to the Suborder Agnostina. In Treatise on Invertebrate Paleontology, Part O, Arthropoda 1. Trilobita, Revised. Volume 1 (ed. Kaesler, R. L.), pp 331–83. Lawrence: Geological Society of America and University of Kansas Press.Google Scholar
Shergold, J. H., Laurie, J. R. & Sun., X. 1990. Classification and review of the trilobite order Agnostida Salter, 1864: an Australian perspective. Bureau of Mineral Resources Geology and Geophysics Australia Report 296, 193.Google Scholar
Šnajdr, M. 1984. Noví trilobiti z Dobrotivskěho Souvrství (Ordovik, Čechy). Časopis Národního Muzea, Paleozoologie 153 146–9.Google Scholar
Stewart, S. & Owen, A. W. 2008. Probing the deep shelf – a Lagerstätte from the Upper Ordovician of Girvan, SW Scotland. Lethaia 41, 139–46.Google Scholar
Suzuki, Y., Shiino, Y & Bergström, J. 2009. Stratigraphy, carbonate facies and trilobite associations in the Hirnantian part of the Boda Limestone, Sweden. GFF 131, 299310.Google Scholar
Thomas, A. T, Owens, R. M. & Rushton, A. W. A. 1984. Trilobites in British stratigraphy. Geological Society of London Special Report 16, 178.Google Scholar
Tripp, R. P., Zhou, Z.-Y. & Pan, Z.-Q. 1989. Trilobites from the Upper Ordovician Tangtou Formation, Jaingsu Province, China. Transactions of the Royal Society of Edinburgh: Earth Sciences 80, 2568.Google Scholar
Turvey, S. T. 2007. Asaphoid trilobites from the Arenig-Llanvirn of the South China Plate. Palaeontology 50, 347–99.Google Scholar
Villas, E., Hammann, W. & Harper, D. A. T. 2002. Foliomena fauna (Brachiopoda) from the Upper Ordovician of Sardinia. Palaeontology 45, 267–95.Google Scholar
Volborth, A. von. 1863. Über die mit glatten Rumpfgliedern versehenen russischen Trilobiten, nebst einem Anhange über die Bewegungsorgane und über das Herz derselben. Mémoires de L’ Academie Impériale des Sciences, St Pétersburg. Series 7, 6 (2), 147.Google Scholar
Wahlenberg, G. 1818. Petrificata telluris Svecanae. Nova Acta Regiae Societatis Scientarium Upsaliensis 8, 1–116.Google Scholar
Waisfeld, B. G., Vaccari, N. E., Chatterton, B. D. E. & Egecombe, G. D. 2001. Systematics of the Shumardiidae (Trilobita), with new species from the Ordovician of Argentina. Journal of Paleontology 75, 827–69.Google Scholar
Warburg, E. 1939. The Swedish Ordovician and lower Silurian Lichidae. Kungliga Svenska Vetenskaps-Akademiens Handlingar 17, 1162.Google Scholar
Weir, J. A. 1959. Ashgill trilobites from Co. Clare. Palaeontology 1, 369–83.Google Scholar
Whittard, W. F. 1955. The Ordovician trilobites of the Shelve inlier, west Shropshire. Part 1.Monograph of the Palaeontographical Society 109 (470), 140, pls 1–4.Google Scholar
Whittard, W. F. 1961. The Ordovician trilobites of the Shelve inlier, west Shropshire. Part 5. Monograph of the Palaeontographical Society 119 (508), 163–96, pls 22–5.Google Scholar
Whittington, H. B. 1941. The Trinucleidae – with special reference to North American genera and species. Journal of Paleontology 15, 2144.Google Scholar
Whittington, H. B. 1950. Sixteen Ordovician genotype trilobites. Journal of Paleontology 24, 531–65.Google Scholar
Whittington, H. B. 1959. Silicified Middle Ordovician trilobites: Remopleurididae, Trinucleidae, Raphiophoridae, Endymioniidae. Bulletin of the Museum of Comparative Zoology at Harvard College 121 (8), 373496.Google Scholar
Whittington, H. B. 1965 a. A monograph of the Ordovician trilobites of the Bala area, Merioneth, 2. Monograph of the Palaeontographical Society 118 (504) 3362, pls 9–18.Google Scholar
Whittington, H. B. 1965 b. Trilobites of the Ordovician Table Head Formation, western Newfoundland. Bulletin of the Museum of Comparative Zoology, Harvard University 132 (4), 275442.Google Scholar
Whittington, H. B. 1966. A monograph of the Ordovician trilobites of the Bala area, Merioneth. 3. Monograph of the Palaeontographical Society 120 (512), 6392.Google Scholar
Whittington, H. B. 1968. A monograph of the Ordovician trilobites of the Bala area, Merioneth. 4. Monograph of the Palaeontographical Society 122 (520), 93138.Google Scholar
Whittington, H. B. 2003. The trilobite Family Nileidae: morphology and classification. Palaeontology 46, 635–46.Google Scholar
Williams, S. H., Boyce, W. D., Colman-Sadd, S. P. 1992. A new Lower Ordovician (Arenig) faunule from the Coy Pond Complex, central Newfoundland, and a refined understanding of the closure of the Iapetus Ocean. Canadian Journal of Earth Sciences 29, 2046–57.Google Scholar
Xiang, L.-W. & Ji, Z.-L. 1987. Upper Ordovician (Middle Ashgillian) trilobites from the Linxiang Formation in southern China. Professional papers of stratigraphy and palaeontology No. 19. Geological Publishing House, pp. 1–25 (in Chinese with English summary).Google Scholar
Yin, G.-Z., Tripp, R. P., Zhou, Z.-Y., Zhou, Z.-Q. & Yuan, W-W. 2000. Trilobites and biofacies of the Ordovician Pagoda Formation, Donggongsi of Zunyi, Guizhou Province, China. Transactions of the Royal Society of Edinburgh: Earth Sciences 90 (for 1999), 203–20.Google Scholar
Zhan, R.-B. & Jin, J. 2005. New data on the Foliomena fauna (Brachiopoda) from the Upper Ordovician of South China. Journal of Paleontology 79, 670–86.Google Scholar
Zhang, S. 2011. Timing and extent of maximum transgression across Laurentia during Late Ordovician: New evidence from Slave Craton, Canadian Shield. Palaeogeography, Palaeoclimatology, Palaeoecology 306, 196204.Google Scholar
Zhou, Z.-Y., Bergström, J., Zhou, Z.-Q., Yuan, W.-W. & Zhang, Y.-B. 2011. Trilobite biofacies and palaeogeographic development in the Arenig (Ordovician) of the Yangtze Block, China. Palaeoworld 20, 1545.Google Scholar
Zhou, Z.-Y. & Dean, W. T. 1986. Ordovician trilobites from Chedao, Gansu Province, north-west China. Palaeontology 29, 743–86.Google Scholar
Zhou, Z.-Y. & Hughes, C. P. 1989. A review of the trinucleid trilobites of China. Paläontologische Zeitschrift 63, 5578.Google Scholar
Zhou, Z.-Y., McNamara, K. J., Yuan, W.-W. & Zhang, T.-R. 1994. Cyclopygid trilobites from the Ordovician of northeastern Tarim, Xinjiang, northwest China. Records of Western Australian Museum 16, 593622.Google Scholar
Zhou, Z.-Y., Yin, G.-Z. & Tripp, R. P. 1984. Trilobites from the Ordovician Shihtzupu Formation, Zunyi, Guizhou Province, China. Transaction of the Royal Society of Edinburgh: Earth Sciences 75, 1336.Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q. 1982. An Ashgill (Rawtheyan) trilobite faunule from Ejin Qi, Nei Mongol (Inner Mongolia). Acta Palaeontologica Sinica 21, 668–71 (in Chinese with English summary).Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q. 2007. The remopleuridine trilobite Amphitryon Hawle & Corda, 1847, from the Pagoda Formation of southwestern Shaanxi, China. Memoirs of the Association of Australian Palaeontologists 34, 173–80.Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q. 2008. Chapter 8. Latest Cambrian and Ordovician. In Trilobite Record of China (eds Zhou, Z.Y. & Zhen, Y.-Y.), pp. 208–74. Beijing: Science Press, 401 pp.Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q. 2009. Ordovician cyclopygid trilobites from the Pagoda Formation of southwestern Shaanxi, China. Memoirs of the Association of Australian Palaeontologists 37, 87101.Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q., Siveter, D. J. & Yuan, W.-W. 2003. Latest Llanvirn to early Caradoc trilobite biofacies of the north-western marginal area of the Yangtze block, China. Special Papers in Palaeontology 70, 281–91.Google Scholar
Zhou, Z.-Y. & Zhou, Z.-Q. & Yuan, W.-W. 2001. Llanvirn-early Caradoc trilobite biofacies of western Hubei and Huna, China. Alcheringa 25, 6986.Google Scholar
Zhou, Z.-Q., Zhou, Z.-Y. & Yuan, W.-W. 2007. Middle Upper Ordovician trilobite biofacies of the northwestern marginal area of the Yangtze Block, China. Acta Palaeontologica Sinica 46 (Supplement), 549–57.Google Scholar

Reference

Budil, P., Fatka, O., Kolář, P. & David, M. 2011. Arthrorhachis Hawle and Corda, 1847 (Agnostida) in the Prague Basin (Barrandian area, Czech Republic) revisited. Bulletin of Geosciences 86, 707–23.Google Scholar