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Emergence, biodiversification and extinction of the chitinozoan group

Published online by Cambridge University Press:  07 July 2010

YNGVE GRAHN*
Affiliation:
Universidade do Estado do Rio de Janeiro, Faculdade de Geologia, Bloco A – Sala 4001, Rua São Francisco Xavier 524, 20550-013 Rio de Janeiro, R.J., Brazil
FLORENTIN PARIS
Affiliation:
Université de Rennes 1, Géosciences Rennes, UMR 6118 du CNRS, 35042 Rennes-cedex, France
*
*Author for correspondence: [email protected]

Abstract

Chitinozoans are considered as reproductive bodies of marine invertebrates, called chitinozoophorans. These chitinozoophorans were most likely to have been small, pelagic or necto-pelagic, soft-bodied, probably wormlike animals, and judging from the size of chitinozoans, they probably measured from a few millimetres to a few centimetres in length. The chitinozoophorans most likely survived by grazing on phytoplankton. There is no evidence of a large colonization of the pelagic niche in the Cambrian, but from the Early Ordovician onward, this niche was exploited chiefly by graptolites and chitinozoophorans. Both groups inhabited nearshore and offshore habitats, but in contrast to the graptolites, the chitinozoans displayed their highest diversity at high latitude, in less distal (that is, upper and lower offshore) environments. The chitinozoan group evolved rapidly during the Ordovician and reached its maximum Ordovician diversity in the late Darriwilian. From the first occurrence of chitinozoans in early Tremadocian times, to the biodiversity crisis in latest Ordovician times, nearly 80 % of the morphological innovations took place. Until their extinction in the latest Devonian, chitinozoans survived through several biodiversity crises: in the early Late Ordovician, late Hirnantian, late Wenlock, earliest Emsian, and in the latest Frasnian (Kellwasser event). During the melting of the Hirnantian ice sheet, most Ordovician genera and species became extinct, but some genera extended beyond the boundary (e.g. Spinachitina, Belonechitina, Cyathochitina, Ancyrochitina). The Hirnantian glaciation was not directly responsible for the dramatic extinction of organic-walled microfossils, but it certainly accelerated the extinction of lineages that had already been weakened since the early to mid-Katian. The late Wenlock and earliest Emsian graptolite crises affected the chitinozoophorans to a lesser degree, and the latest Frasnian Kellwasser event did not greatly affect chitinozoophorans. The disappearance of the chitinozoan group at the end of the Famennian resulted from a combination of factors, for example, the chitinozoophorans probably no longer had the genetic potential for successful adaptations to successive drastic environmental changes (only one species is known from the latest Famennian), their usual niche was invaded by more efficient groups, and their usual food supply disappeared or was no longer sufficient. The latter factor is supported by the contemporaneous decline in phytoplankton.

Type
Original Article
Copyright
Copyright © Cambridge University Press 2010

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References

Abdesselam-Rouighi, F. F. & Coquel, R. 1997. Palynologie du Dévonien terminal–Carbonifère inférieur dans le Sud-Est du bassin d'Illizi (Sahara algérien). Position des premières lycospores dans la série stratigraphique. Annales de la Société Géologique du Nord T.5 (2eme sér.), 4757.Google Scholar
Achab, A. 1981. Biostratigraphie par les Chitinozoaires de l'Ordovicien supérieur–Silurien inférieur de l'Ile d'Anticosti. Résultats préliminaires. In Subcommission on Silurian stratigraphy, Ordovician–Silurian Boundary Working Group (ed. Lespérance, P. J.), pp. 143–57. Field Meeting, Anticosti – Gaspé, Quebec, 1981. II. Stratigraphy and Paleontology.Google Scholar
Achab, A., Asselin, E. & Desrochers, A. 2008. Revisiting the Upper Ordovician chitinozoan assemblages from Anticosti Island: implications for local, regional and global correlation. In Paleozoic Climates (eds Kröger, B. & Servais, T.), p. 11. Abstracts, International Congress – Congrès international, August 22–31, 2008, Lille, France.Google Scholar
Achab, A. & Paris, F. 2007. The Ordovician chitinozoan biodiversification and its leading factors. Palaeogeography Palaeoclimatology Palaeoecology 245, 519.CrossRefGoogle Scholar
Ainsaar, L., Kaljo, D., Martma, T., Meidla, T., Männik, P., Nõlvak, J. & Tinn, O. 2010. Middle and Upper Ordovician carbon isotope chemostratigraphy in Baltoscandia: a correlation standard and clues to environmental history. Palaeogeography, Palaeoclimatology, Palaeoecology, 13 pp. Doi:10.1016/j;palaeo.2010.01.003.Google Scholar
Ainsaar, L., Meidla, T. & Martna, T. 2004. The Middle Caradoc facies and faunal turnover in the Late Ordovician Baltoscandian paleobasin. Palaeogeography Palaeoclimatology Palaeoecology 210, 119–33.CrossRefGoogle Scholar
Averbuch, O., Tribovillard, N., Devleeschouwer, X., Riquier, L., Mistiaen, B. & van Vliet-Lanoe, B. 2005. Mountain building-enhanced continental weathering and organic carbon burial as major causes for climatic cooling at the Frasnian–Fammenian boundary (c. 376 Ma)? Terra Nova 17, 2534.CrossRefGoogle Scholar
Bergström, S. M., Chen, X., Gutiérrez-Marco, J. C. & Dronov, A. 2009 a. The new chronostratigraphic classification of the Ordovician System and its relations to major regional series and stages and to δ13C chemostratigraphy. Lethaia 42, 97107.CrossRefGoogle Scholar
Bergström, S. M., Chen, X., Schmitz, B., Young, S., Rong, J. Y. & Saltzman, M. R. 2009 b. First documentation of the Ordovician Guttenberg δ13C excursion (GICE) in Asia: chemostratigraphy of the Pagoda and Yanwashan formations in southeastern China. Geological Magazine 146, 657–78.CrossRefGoogle Scholar
Bergström, S. M., Saltzman, M. M. & Schmitz, B. 2006. First record of the Hirnantian (Upper Ordovician) δ13C excursion in the North American Midcontinent and its regional implications. Geological Magazine 143, 657–78.CrossRefGoogle Scholar
Bloeser, B., Scopf, J. W., Hordystir, R. J. & Breed, W. J. 1977. Chitinozoans from the Late Precambrian Chuar group of the Grand Canyon, Arizona. Science 195, 676–9.CrossRefGoogle ScholarPubMed
Boumendjel, K., Loboziak, S., Paris, F., Steemans, P. & Streel, M. 1988. Biostratigraphy des miospores et des chitinozoaires du Silurien supérieur et du Dévonien dans le Bassin d'Illizi (S.E. du Sahara algérien). Geobios 21, 329–57.CrossRefGoogle Scholar
Bourahrouh, A., Paris, F. & Elaouad-Debbaj, Z. 2004. Biostratigraphy, biodiversity and palaeoenvironments of the chitinozoans and associated palynomorphs from the Upper Ordovician of the Central Anti-Atlas, Morocco. Review of Palaeobotany and Palynology 130, 1740.CrossRefGoogle Scholar
Brett, C. A. & Baird, G. C. 1986. Comparative taphonomy: a key to paleoenvironmental interpretation based on fossil preservation. Palaios 1, 207–27.CrossRefGoogle Scholar
Burke, W. H., Denison, R. E., Hetherington, E. A., Koepnick, R. B., Nelson, H. F. & Otto, J. B. 1982. Variation of seawater 87Sr/86Sr through Phanerozoic time. Geology 10, 516–9.2.0.CO;2>CrossRefGoogle Scholar
Chen, X. H., Paris, F. & Zhang, M. 2008. Chitinozoans from the Fenxiang Formation (Early Ordovician) of Yichang, Hubei Province, China. Acta Geologica Sinica 82, 287–94.Google Scholar
Chlupáč, I. & Kukal, Z. 1988. Possible global events and the stratigraphy of the Palaeozoic of the Barrandian (Cambrian – Middle Devonian, Czechoslovakia). Sbornik geologichych věd Geologie 43, 83146.Google Scholar
Collinson, C. & Schwalb, H. 1955. North American Paleozoic Chitinozoa. Illinois State Geological Survey Report of Investigations 186, 33 pp.Google Scholar
Combaz, A. 1967. Un microbios du Trémadocien dans un sondage d'Hassi-Messaoud. Actes de la Société Linnéenne de Bordeaux 104, 126.Google Scholar
Cooper, R. A. 1999. Ecostratigraphy, zonation and global correlation of earliest Ordovician planktic graptolites. Lethaia 32, 116.CrossRefGoogle Scholar
Cooper, R. A., Fortey, R. A. & Lindholm, K. 1991. Latitudinal and depth zonation of Early Ordovician graptolites. Lethaia 24, 199218.CrossRefGoogle Scholar
Corfield, R. M. & Siveter, D. J. 1992. Carbon isotope change as indicator of biomass flue and an aid of correlation during ludensisnilssoni (Silurian) time. Proceedings of the Estonian Academy of Sciences Geology 41, 173–81.CrossRefGoogle Scholar
Corfield, R. M., Siveter, D. J., Cartlidge, J. E. & McKerrow, S. 1992. Carbon isotope excursion near the Wenlock–Ludlow (Silurian) boundary in the Anglo-Welsh area. Geology 20, 371–4.2.3.CO;2>CrossRefGoogle Scholar
Dabard, M. P., Loi, A. & Paris, F. 2007. Relationship between phosphogenesis and sequence architecture: sequence stratigraphy and biostratigraphy in the Middle Ordovician of the Armoricain Massif (NW France). Palaeogeography Palaeoclimatology Palaeoecology 248, 339–56.CrossRefGoogle Scholar
De la Puente, S. & Rubinstein, C. 2009. Late Tremadocian chitinozoans and acritarchs from northwestern Argentina (Western Gondwana). Review of Palaeobotany and Palynology 154, 6578.CrossRefGoogle Scholar
Destombes, J., Holland, C. H. & Willefert, S. 1985. Lower Palaeozoic rocks of Morocco. In Lower Palaeozoic Rocks of the World. Vol. 4, Lower Palaeozoic Rocks of Northwest and West-Central Africa (ed. Holland, C. H.), pp. 91336. Chichester: John Wiley and Sons.Google Scholar
Eisenack, A. 1931. Neue Mikrofossilien des baltischen Silurs. 1. Paläontologische Zeitung 13, 74118.CrossRefGoogle Scholar
Eisenack, A. 1955. Neue Chitinozoen aus dem Silur des Baltikums und dem Devon der Eifel. Senckenbergiana Lethaea 36, 311–9.Google Scholar
Eisenack, A. 1968. Über Chitinozoen des baltischen Gebietes. Palaeontographica Abteilung A 131, 137–98.Google Scholar
Elaouad-Debbaj, Z. 1988. Acritarches et Chitinozoaires du Tremadoc de l'Anti-Atlas central (Maroc). Revue de Micropaléontologie 31, 85128.Google Scholar
Elick, J. M., Driese, S. G. & Mora, C. I. 1998. Very large plant and root traces from the Early to Middle Devonian: implications for early terrestrial ecosystems and atmospheric p(CO2). Geology 26, 143–6.2.3.CO;2>CrossRefGoogle Scholar
Filipiak, P. 2002. Palynofacies around the Frasnian/Famennian boundary in the Holy Cross Mountains, southern Poland. Palaeogeography Palaeoclimatology Palaeoecology 181, 313–24.CrossRefGoogle Scholar
Grahn, Y. 1978. Chitinozoan stratigraphy and palaeoecology of the Ordovician–Silurian boundary in Skåne, southern Sweden. Sveriges Geologiska Undersökning Serie C 766, 116.Google Scholar
Grahn, Y. 1981. Ordovician Chitinozoa from the Stora Åsbotorp boring in Västergötland, south-central Sweden. Sveriges Geologiska Undersökning Serie C 787, 140.Google Scholar
Grahn, Y. 1984 a. Ordovician Chitinozoa from Tallinn, northern Estonia. Review of Palaeobotany and Palynology 43, 531.CrossRefGoogle Scholar
Grahn, Y. 1984 b. Early Caradoc Chitinozoa from Östergötland, south central Sweden. Geologiska Föreningen i Stockholm Förhandlingar 105, 269–72.CrossRefGoogle Scholar
Grahn, Y. 1998. Lower Silurian (Llandovery–middle Wenlock) Chitinozoa and biostratigraphy of the mainland of Sweden. GFF 120, 273–83.CrossRefGoogle Scholar
Grahn, Y. 2005. Silurian and Lower Devonian chitinozoan taxonomy and biostratigraphy of the Trombetas Group, Amazonas Basin, Northern Brazil. Bulletin of Geosciences 80, 245–76.Google Scholar
Grahn, Y. & Afzelius, B. A. 1980. Ultrastructural studies of some chitinozoan vesicles. Lethaia 13, 119–26.CrossRefGoogle Scholar
Grahn, Y. & Caputo, M. V. 1992. Early Silurian glaciations in Brazil. Palaeogeography Palaeoclimatology Palaeoecology 99, 915.CrossRefGoogle Scholar
Grahn, Y., Loboziak, S. & Melo, J. H. G. 2003. Integrated correlation of Late Silurian (Pridoli s.l.) – Devonian chitinozoans and miospores in the Solimões Basin, northern Brazil. Acta Geologica Polonica 53, 283300.Google Scholar
Grahn, Y. & Melo, J. H. G. 2002. Chitinozoan biostratigraphy of the Late Devonian formations in well Caima PH-2, Tapajós River area, Amazonas Basin, northern Brazil. Review of Palaeobotany and Palynology 118, 116–40.CrossRefGoogle Scholar
Grahn, Y. & Nõlvak, J. 2007 a. Remarks on older Ordovician Chitinozoa and biostratigraphy of the Oslo Region, southern Norway. GFF 129, 101–6.CrossRefGoogle Scholar
Grahn, Y. & Nõlvak, J. 2007 b. Ordovician Chitinozoa and biostratigraphy from Skåne and Bornholm, southernmost Scandinavia – an overview and update. Bulletin of Geosciences 82, 1126.CrossRefGoogle Scholar
Grahn, Y. & Nõlvak, J. 2010. Swedish Ordovician Chitinozoa and biostratigraphy: a review and new data. Palaeontographica Abteilung B 283 (1–3), 167.Google Scholar
Hamoumi, N. 1999. Upper Ordovician glaciation spreading and its sedimentary record in Moroccan North Gondwana margin. Acta Universitatis Carolinae, Geologica 43, 111–14.Google Scholar
Heuse, T., Grahn, Y. & Erdtmann, B.-D. 1999. Early Ordovician chitinozoans from the east Precordillera of southern Bolivia. Revue de Micropaléontologie 42, 4355.CrossRefGoogle Scholar
Hints, O., Delabroye, A., Nõlvak, J., Servais, T., Uutela, A. & Wallin, Å. 2010. Biodiversity patterns of Ordovician marine phytoplankton from Baltica: comparison with other fossil groups and sea-level changes. Palaeogeography Palaeoclimatology Palaeoecology, 13 pp. Doi:10.1016/j;palaeo.2009.11.003.Google Scholar
Hints, O. & Nõlvak, J. 2006. Early Ordovician scolecodonts and chitinozoans from Tallinn, north Estonia. Review of Palaeobotany and Palynology 139, 189209.CrossRefGoogle Scholar
House, M. R. 2002. Strength, timing and cause of mid-Palaeozoic extinctions. Palaeogeography Palaeoclimatology Palaeoecology 181, 525.CrossRefGoogle Scholar
Jacob, J., Paris, F., Monod, O., Miller, M. A., Tang, P., George, S. C. & Bény, J.-M. 2007. New insights into the chemical composition of the chitinozoans. Organic Geochemistry 38, 1782–8.CrossRefGoogle Scholar
Jaeger, H. 1978. Late graptoloid faunas and the problem of graptoloid extinction. Acta Palaeontologica Polonica 23, 497521.Google Scholar
Jaeger, H. 1991. Neue Standard-Graptolithenzonenfolge nach der “Grosen Krise” an der Wenlock/Ludlow-Grenze (Silur). Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 182, 303–54.CrossRefGoogle Scholar
Jenkins, W. A. M. 1970. Chitinozoa. Geoscience and Man 1, 21 pp.CrossRefGoogle Scholar
Jeram, A. J., Selden, P. A. & Edwards, D. 1990. Land animals in the Silurian: arachnids and myriapods from Shropshire, England. Science 250, 658–61.CrossRefGoogle ScholarPubMed
Joachimski, M. M., Pancost, R. D., Freeman, K. H., Ostertag-Henning, C. & Buggisch, W. 2002. Carbon isotope geochemistry of the Frasnian–Famennian transition. Palaeogeography Palaeoclimatology Palaeoecology 181, 91109.CrossRefGoogle Scholar
Johnson, M. E., Kaljo, D. L. & Rong, J. Y. 1991. Silurian eustasy. In The Murchison Symposium: Proceedings of an International Conference on the Silurian System (eds Bassett, M. G., Lane, P. D. & Edwards, D.), pp. 145–63. Special Papers in Palaeontology 44.Google Scholar
Johnson, M. E. & McKerrow, W. S. 1991. Sea level and faunal changes during the latest Llandovery and earliest Ludlow (Silurian). Historical Biology 5, 153–69.CrossRefGoogle Scholar
Kaljo, D. L., Hints, L., Männik, P. & Nõlvak, J. 2008. The succession of Hirnantian events based on data from Baltica: brachiopods, chitinozoans, conodonts, and carbon isotopes. Estonian Journal of Earth Sciences 57, 197218.CrossRefGoogle Scholar
Kaljo, D. L., Kiipli, T. & Martma, T. 1998. Correlation of carbon isotope events and environmental cyclicity in the East Baltic Silurian. In Silurian Cycles – Linkages of Dynamic Stratigraphy with Atmospheric, Oceanic and Tectonic Changes (eds Landing, E. & Johnson, M.), pp. 297312. New York State Museum Bulletin no. 491.Google Scholar
Kaljo, D. L. & Märss, T. 1991. Pattern of some Silurian bioevents. Historical Biology 5, 145–52.CrossRefGoogle Scholar
Koren, T. N. & Urbanek, A. 1994. Adaptive radiation of monograptids after the late Wenlock crisis. Acta Geologica Polonica 39, 137–67.Google Scholar
Kozlowska-Dawidziuk, A., Lenz, A. C. & Štorch, P. 2001. Upper Wenlock and Lower Ludlow (Silurian) post-extinction graptolites, Všeradice Section, Barrandian area, Czech Republic. Journal of Paleontology 75, 147–64.2.0.CO;2>CrossRefGoogle Scholar
Kozlowski, R. 1963. Sur la nature des Chitinozoaires. Acta Paleontologica Polonica 8, 425–49.Google Scholar
Le Hérissé, A., Bourahrouh, A., Vecoli, M. & Paris, F. 2003. Palynological tracers of sea-ice cover extent during the latest Ordovician on the North African margin. AAPG Hedberg conference. Paleozoic and Triassic petroleum systems in North Africa, February 18–20, Algiers, Algeria, pp. 1–2.Google Scholar
Lehnert, O., Männik, P., Joachimski, M. M., Calner, M. & Fryda, J. 2010. Palaeoclimate perturbations before the Sheinwoodian glaciation: a trigger for extinctions during the “Ireviken Event”. Palaeogeography Palaeoclimatology Palaeoecology, 12 pp. Doi:10.1016/j.palaeo.2010.01.009.Google Scholar
Lethiers, F., Baudin, F. & Casier, J. G. 1998. Ostracodes de la limite Frasnien–Famennien en environment anoxique (La Serre, Montagne Noire, France). Revue de Micropaléontologie 41, 321–36.CrossRefGoogle Scholar
Lethiers, F. & Raymond, D. 1991. Les crises du Dévonien supérieur par l’étude des faunes d'ostracodes dans leur cadre paléogéographique. Palaeogeography Palaeoclimatology Palaeolecology 88, 133–46.CrossRefGoogle Scholar
Loboziak, S., Melo, J. H. G., Quadros, L. P. & Streel, M. 1997. Palynological evaluation of the Famennian Protosalvinia (Foerstia) Zone in the Amazonas Basin, northern Brazil: a preliminary study. Review of Palaeobotany and Palynology 96, 3145.CrossRefGoogle Scholar
Loi, A., Ghienne, J. F., Dabard, M. P., Paris, F., Botquelen, A., Christ, N., Elaouad-Debbaj, Z., Gorini, A., Vidal, M. & Videt, B. 2010. The Late Ordovician glacio-eustatic record from a high-latitude storm-dominated shelf succession: the Bou Ingarf section (Anti-Atlas, Southern Morocco). Palaeogeography, Palaeoclimatology, Palaeoecology, 27 pp. Doi: 10.1016/j.palaeo.2010.01.018.Google Scholar
McGhee, G. R. 2001. The “multiple impacts hypothesis” for mass extinction: a comparison of the Late Devonian and the late Eocene. Palaeogeography Palaeoclimatology Palaeoecology 176, 4758.CrossRefGoogle Scholar
Melchin, M. J. 2008. Restudy of some Ordovician–Silurian boundary graptolites from Anticosti Island, Canada, and their biostratigraphic significance. Lethaia 41, 155–62.CrossRefGoogle Scholar
Meyer-Berthaud, B., Scheckler, S. E. & Wendt, J. 1999. Archaeopteris is the earliest known modern tree. Nature 398, 700–1.CrossRefGoogle Scholar
Morrissey, L. B. & Braddy, S. J. 2004. Terrestrial trace fossils from the Lower Old Red Sandstone, southwest Wales. Geological Journal 39, 315–36.CrossRefGoogle Scholar
Nestor, V. 2009. Chitinozoan diversity in the East Baltic Silurian. Estonian Journal of Earth Sciences 58, 311–6.CrossRefGoogle Scholar
Niklas, K. J., Phillips, T. L. & Carozzi, A. V. 1976. Morphology and paleoecology of Protosalvinia from the Upper Devonian (Famennian) of the Middle Amazon Basin of Brazil. Palaeontographica Abteilung B 155, 130.Google Scholar
Nõlvak, J. 1999. Ordovician chitinozoan biozonation of Baltoscandia. Acta Universitatis Carolinae, Geologica 43, 287–90.Google Scholar
Nõlvak, J. & Grahn, Y. 1993. Ordovician chitinozoan zones from Baltoscandia. Review of Palaeobotany and Palynology 79, 245–69.CrossRefGoogle Scholar
Ogg, J. G., Ogg, G. & Gradstein, F. M. 2008. Concise Geologic Time Scale. Cambridge University Press, 177 pp.Google Scholar
Paris, F. 1981. Les Chitinozoaires dans le Paléozoïque du sud-ouest de l'Europe (cadre géologique – étude systématique – biostratigraphie). Mémoire de la Société géologique et minéralogique de Bretagne 26, 492 pp.Google Scholar
Paris, F. 1984. Bassins paléozoïques caches d'Aquitaine; biostratigraphie par les Chitinozoaires, Ostracodes, Tentaculites. Documents de BRGM, 13–17.Google Scholar
Paris, F. 1990. The Ordovician chitinozoan biozones of the Northern Gondwana Domain. Review of Palaeobotany and Palynology 66, 181209.CrossRefGoogle Scholar
Paris, F., Achab, A., Asselin, E., Chen, X.-H., Grahn, Y., Nõlvak, J., Obut, O., Sennikov, N., Vecoli, M., Verniers, J., Wang, X.-F. & Winchester-Seeto, T. 2004. Chapter 28: Chitinozoans. In The Great Ordovician Biodiversification Event (eds Webby, B. D., Paris, F., Droser, M. L. & Percival, I. G.), pp. 294311. New York: Columbia University Press.CrossRefGoogle Scholar
Paris, F. & Bernard, D. 1994. “PHOTOCHITINO”, an image-incorporated electronic database for chitinozoan identification. In CIMP Symposium on Palynology, Palaeoenvironments and Stratigraphy (eds Dorning, K. et al. ), p. 32. Abstract. Sheffield, 7–10 September 1994.Google Scholar
Paris, F., Bourahrouh, A. & le Hérissé, A. 2000. The effects of the final stages of the Late Ordovician glaciation on marine palynomorphs (chitinozoans, acritarchs, leiospheres) in well NI-2 (NE Algerian Sahara). Review of Palaeobotany and Palynology 113, 87104.CrossRefGoogle Scholar
Paris, F., Girard, C., Feist, C. & Winchester-Seeto, T. 1996. Chitinozoan bio-event in the Frasnian/Famennian boundary beds at La Serre (Montagne Noire, Southern France). Palaeogeography Palaeoclimatology Palaeoecology 121, 131–45.CrossRefGoogle Scholar
Paris, F., Grahn, Y., Nestor, V. & Lakova, I. 1999. Proposal for a revised chitinozoan classification. Journal of Paleontology 73, 549–70.CrossRefGoogle Scholar
Paris, F. & Nõlvak, J. 1999. Biological interpretation and paleobiodiversity of a cryptic fossil group: the “Chitinozoan animal”. Geobios 32, 315–24.CrossRefGoogle Scholar
Paris, F., Winchester-Seeto, T., Boumendjel, K. & Grahn, Y. 2000. Toward a global biozonation of Devonian chitinozoans. Courier Forschungsinstitut Senckenberg 220, 3955.Google Scholar
Perrier, V. J., Vannier, D. J. & Siveter, D. J. 2007. The Silurian pelagic myodocope ostracode Richteria migrans. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 98, 151–63.CrossRefGoogle Scholar
Porter, S. M. & Knoll, A. H. 2000. Testate amoebae in the Neoproterozoic Era: evidence from vase-shaped microfossils in the Chuar group, Grand Canyon. Paleobiology 26, 360–85.2.0.CO;2>CrossRefGoogle Scholar
Porter, S. M., Meisterfeld, R. & Knoll, A. H. 2003. Vase-shaped microfossils from the Neoproterozoic Chuar Group, Grand Canyon: a classification guided by modern testate amoebae. Journal of Paleontology 77, 409–29.2.0.CO;2>CrossRefGoogle Scholar
Poumot, C. 1964. Trois nouveaux genres de Chitinozoaires de l'Ordovicien. Documents internes CIMP(1965), 62–75.Google Scholar
Poumot, C. 1968. Amphorachitina, Ollachitina, Velatachitina, Trois nouveaux Genres de Chitinozoaires de l'Erg Oriental (Algérie-Tunisie). Bulletin centre de recherches. Elf exploration production, Pau 2, 4555.Google Scholar
Pujol, F., Berner, Z. & Stüben, D. 2006. Palaeoenvironmental changes at the Frasnian/Famennian boundary in key European sections: chemostratigraphic constraints. Palaeogeography Palaeoclimatology Palaeoecology 240, 120–45.CrossRefGoogle Scholar
Quinby-Hunt, M. S. & Berry, W. B. N. 1991. Late Wenlock (Middle Silurian) Global bioevent: possible chemical cause for mass graptolite mortalities. Historical Biology 5, 171–81.CrossRefGoogle Scholar
Racki, G. 1998. Frasnian–Famennian biotic crisis: undervaluated tectonic control? Palaeogeography Palaeoclimatology Palaeoecology 141, 177–98.CrossRefGoogle Scholar
Racki, G., Racka, M., Matyja, H. & Devleeschouwer, X. 2002. The Frasnian/Famennian boundary interval in the South Polish–Moravian shelf basins: integrated event–stratigraphical approach. Palaeogeography Palaeoclimatology Palaeoecology 181, 251–97.CrossRefGoogle Scholar
Riegel, W. 2008. The Late Palaeozoic phytoplankton blackout – artefact or evidence of global change? Review of Palaeobotany and Palynology 148, 7390.CrossRefGoogle Scholar
Sadler, P. M., Cooper, R. A. & Melchin, M. 2009. High-resolution, early Paleozoic (Ordovician–Silurian) time scales. Geological Society of America Bulletin 121, 887906.CrossRefGoogle Scholar
Samuelsson, J. 1999. Ordovician Chitinozoa from Rügen, North-East Germany. In Quo Vadis Ordovician? 8th International Symposium on Ordovician System, Prague (eds Kraft, P. & Fatka, O.), pp. 295–7. Acta Universitatis Carolinae, Geologica 43.Google Scholar
Sennikov, N. V., Yolkin, E. A., Petrunina, Z. E., Gladkikh, L. A., Obut, O. T., Izokh, N. G. & Kipriyanova, T. P. 2008. Ordovician–Silurian biostratigraphy and paleogeography of the Gorny Altai. In Trofimuk Institute of Petroleum Geology and Geophysics Sb Ras (eds Sennikov, A. V. & Kanygin, A. V.), pp. 1156. Novosibirsk; Publishing House Sb Ras.Google Scholar
Servais, T., Lehnert, O., Li, J., Mullins, G. L., Munnecke, A., Nützel, A. & Vecoli, M. 2008. The Ordovician biodiversification: revolution in the oceanic trophic chain. Lethaia 41, 99109.CrossRefGoogle Scholar
Siveter, D. J., Vannier, D. J. & Palmer, M. C. 1991. Silurian myodocopes: pioneer pelagic ostracodes and the chronology of an ecological shift. Journal of Micropalaeontology 10, 151–73.CrossRefGoogle Scholar
Soufiane, A. & Achab, A. 2000. Chitinozoan zonation of the Late Ordovician and the Early Silurian of the island of Anticosti, Québec, Canada. Review of Palaeobotany and Palynology 109, 85111.CrossRefGoogle ScholarPubMed
Stanley, G. D. Jr & Sturmer, W. 1983. The first fossil ctenophore from the Lower Devonian of West Germany. Nature 303, 518–20.CrossRefGoogle Scholar
Štorch, P. 1995. Biotic crisis and post-crisis recoveries recorded by Silurian planktonic graptolite faunas of the Barrandian area (Czech Republic). Geolines (Praha) 3, 5970.Google Scholar
Streel, M., Caputo, M. V., Loboziak, S. & Melo, J. H. G. 2000. Late Frasnian–Famennian climates based on palynomorph analyses and the question of the Late Devonian glaciations. Earth Science Reviews 52, 121–73.CrossRefGoogle Scholar
Tasch, P. & Hutter, T. J. 1978. Pennsylvanian chitinozoans from Eastern Kansas. Palinologia, núm. extraord. 1, 443–52.Google Scholar
Trotter, J. A., Williams, I. S., Barns, C. R., Lécuyer, C. & Nicoll, R. S. 2008. Did cooling oceans trigger Ordovician biodiversification? Evidence from conodont thermometry. Science 321, 550–4.CrossRefGoogle ScholarPubMed
Vandenbroucke, T., Armstrong, H. A., Williams, M., Paris, F., Sabbe, K., Zalasiewicz, J. A. & Nõlvak, J. 2010. Epipelagic chitinozoan biotopes map a steep latitudinal temperature gradient for earliest Late Ordovician seas: implications for a cooling Late Ordovician climate. Palaeogeography Palaeoclimatology Palaeoecology, 18 pp. Doi: 10.1016/j.palaeo.2009.11.026.Google Scholar
Vandenbroucke, T., Armstrong, H. A., Williams, M., Zalasiewicz, J. A. & Sabbe, K. 2009 a. Ground-truthing Late Ordovician climate models using the paleobiogeography of graptolites. Paleoceanography 24, PA 4202.CrossRefGoogle Scholar
Vandenbroucke, T., Gabbott, S. E., Paris, F., Aldridge, R. J. & Theron, J. N. 2009 b. Chitinozoans and the age of the Soom Shale, an Ordovician black shale Lagerstätte, South Africa. Journal of Micropalaeontology 28, 5366.CrossRefGoogle Scholar
Veizer, J., Buhl, D., Diener, A., Ebeneth, S., Podlaha, O. G., Bruckschen, P., Jasper, T., Korte, C., Schaaf, M., Ala, D. & Azmy, K. 1997. Strontium isotope stratigraphy: potential resolution and event correlation. Palaeogeography Palaeoclimatology Palaeoecology 132, 6577.CrossRefGoogle Scholar
Verniers, J. & Vandenbroucke, T. 2006. Chitinozoan biostratigraphy in the Dob's Linn Ordovician–Silurian GSSP, Southern Uplands, Scotland. GFF 128, 195202.CrossRefGoogle Scholar
Videt, B., Paris, F., Rubino, J.-L., Boumendjel, K., Dabard, M.-P., Loi, A. & Ghienne, J.-F. 2010. Calibration of Ordovician sequences on the northern Gondwana platform. Palaeogeography Palaeoclimatology Palaeoecology, Doi: 10.1016/j.palaeo.2010.03.050, in press.CrossRefGoogle Scholar
Villeneuve, M., Diallo, M. C., Keleba, F., Kourouma, S., Paris, F. & Racheboeuf, P. R. 1989. Données paléontologiques nouvelles sur le Paléozoïque du Bassin Bové (Guinée, Afrique de l'Ouest): conséquences stratigraphiques. Comptes rendus de l'Académie des Sciences de Paris 309, 1583–90.Google Scholar
Voss-Foucart, M. F. & Jeuniaux, C. 1972. Lack of chitin in a sample of Ordovician Chitinozoa. Journal of Paleontology 46, 769–70.Google Scholar
Williams, S. H., Nowlan, G. S., Barnes, C. R. & Batten, R. S. R. 1999. The Ledge section at Cow Head, western Newfoundland: new data and discussion of the graptolite, conodont and chitinozoan assemblages. Acta Universitatis Carolinae, Geologica 43, 65–8.Google Scholar
Yolkin, E. A., Kim, A. I., Weddige, K., Talent, J. A. & House, M. R. 2000. The basal Emsian GSSP in Zinzil'ban Gorge, Uzbekistan. Courier Forschungsinstitut Senckenberg 225, 1725.Google Scholar
Zhu, M.-Y., Badcock, L. E. & Peng, S.-C. 2006. Advances in Cambrian stratigraphy and paleontology: integrating correlation techniques, paleobiology, taphonomy and paleoenvironmental reconstruction. Palaeoworld 15, 217–22.CrossRefGoogle Scholar