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Taphonomy of diploporite (Echinodermata) holdfasts from a Silurian hardground, southeastern Indiana, United States: palaeoecologic and stratigraphic significance

Published online by Cambridge University Press:  19 September 2013

JAMES R. THOMKA  and
CARLTON E. BRETT
JAMES R. THOMKA*
Affiliation:
Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221, USA
CARLTON E. BRETT
Affiliation:
Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221, USA
*
*Author for correspondence: [email protected]
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Abstract

A microbioherm-bearing hardground within the middle Silurian (Wenlock) Massie Formation near Napoleon, southeastern Indiana, United States is encrusted by the attachment structures of numerous pelmatozoan echinoderms. Among the most common of these holdfasts are multi-plated discoidal structures representing the thecal attachments of diploporite ‘cystoids’. This large population of holdfasts permits the first detailed taphonomic and palaeoecologic study of hardground diploporite attachments, allowing for increased morphological understanding of these rarely studied structures and facilitating identification of holdfasts in deposits where they might have been overlooked or misidentified. The biostratinomic sequence commences with detachment of thecae, followed by weathering of isolated discoidal holdfasts to bring out radiating canal structures and plate sutures, eventually leading to removal of the interior floor to expose the underlying substrate. Continued exposure can result in separation of component holdfast plates, though cementation to the substrate prevents scattering of plates. Diagenetic precipitation of pyrite occurred after burial; the large size of crystals suggests late diagenesis, perhaps seeded by early diagenetic pyrite crystallites produced by decay of ligamentary tissue. Extrinsic taphonomic factors include overgrowth of holdfasts by laminar stenolaemate bryozoans and other echinoderm attachment structures. Diploporite holdfasts are not bored and are absent on microbioherms. Taphonomic data indicate the time-averaged nature of this hardground and its diploporite assemblage and permit prediction of similar occurrences at major flooding surfaces.

Keywords

Diploporitaattachment structuresencrustationWenlockHolocystites fauna
Type
Original Articles
Information
Geological Magazine , Volume 151 , Issue 4 , July 2014 , pp. 649 - 665
Copyright
Copyright © Cambridge University Press 2013 

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References

Allison, P. A. 1988. Konservat-Lagerstätten: cause and classification. Paleobiology 14, 331–44.Google Scholar
Allison, P. A. 1990. Variation in rates of decay and disarticulation of Echinodermata: implications for the application of actualistic data. Palaios 5, 432–40.Google Scholar
Allison, P. A. & Briggs, D. E. G. 1991. Taphonomy of non-mineralized tissues. In Taphonomy: Releasing the Data Locked in the Fossil Record (eds Allison, P. A. & Briggs, D. E. G.), pp. 25–70. New York: Plenum Press.CrossRefGoogle Scholar
Archer, A. W. & Feldman, H. R. 1986. Microbioherms of the Waldron Shale (Silurian, Indiana): implications for organic framework in Silurian reefs of the Great Lakes area. Palaios 1, 133–40.CrossRefGoogle Scholar
Ausich, W. I. 1975. A paleontological review of the site of Clifty Creek Lake, Wabash River Basin, Indiana. Report to United States Army Corps of Engineers under contract DACW27-75-C-0079, pp. 1–52.Google Scholar
Ausich, W. I. 2001. Echinoderm taphonomy. In Echinoderm Studies 6 (eds Jangoux, M. & Lawrence, J. M.), pp. 171–227. Rotterdam: A. A. Balkema.Google Scholar
Ausich, W. I., Bartels, C. & Kammer, T. K. 2013. Tube foot preservation in the Devonian crinoid Codiacrinus from the Lower Devonian Hunsrück Slate, Germany. Lethaia 46, 416–20.Google Scholar
Brett, C. E. 1978 a. Host-specific pit-forming epizoans on Silurian crinoids. Lethaia 11, 217–32.Google Scholar
Brett, C. E. 1978 b. Attachment structures in the rhombiferan Caryocrinites and their paleobiological implications. Journal of Paleontology 52, 717–26.Google Scholar
Brett, C. E. 1981. Terminology and functional morphology of attachment structures in pelmatozoan echinoderms. Lethaia 14, 343–70.Google Scholar
Brett, C. E. 1984. Autecology of Silurian pelmatozoan echinoderms. In Autecology of Silurian Organisms (eds Bassett, M. G. & Lawson, J. D.), pp. 87–120. Special Papers in Palaeontology 32.Google Scholar
Brett, C. E. 1985. Tremichnus: a new ichnogenus of circular-parabolic pits in fossil echinoderms. Journal of Paleontology 59, 625–35.Google Scholar
Brett, C. E. 1988. Paleoecology and evolution of marine hard substrate communities: an overview. Palaios 3, 374–8.Google Scholar
Brett, C. E. 1991. Organism-sediment relationships in Silurian marine environments. In The Murchison Symposium: Proceedings of an International Symposium on the Silurian System (eds Bassett, M. G., Lane, E. D. & Edwards, D.), pp. 301–44. Special Papers in Palaeontology 44.Google Scholar
Brett, C. E. 1995. Sequence stratigraphy, biostratigraphy, and taphonomy in shallow marine environments. Palaios 10, 597–616.Google Scholar
Brett, C. E. & Baird, G. C. 1986. Comparative taphonomy: a key to paleoenvironmental interpretation based on fossil preservation. Palaios 1, 207–27.CrossRefGoogle Scholar
Brett, C. E., Cramer, B. D., McLaughlin, P. I., Kleffner, M. A., Showers, W. J. & Thomka, J. R. 2012. Revised Telychian-Sheinwoodian (Silurian) stratigraphy of the Laurentian mid-continent: building uniform nomenclature along the Cincinnati Arch. Bulletin of Geosciences 87, 733–53.Google Scholar
Brett, C. E., Deline, B. & McLaughlin, P. I. 2008. Attachment, facies distribution, and life history strategies in crinoids from the Upper Ordovician of Kentucky. In Echinoderm Paleobiology (eds Ausich, W. I. & Webster, G. D.), pp. 22–52. Bloomington: Indiana University Press.Google Scholar
Brett, C. E., Frest, T. J., Sprinkle, J. & Clement, C. R. 1983. Coronoidea: a new class of blastozoan echinoderms based on taxonomic reevaluation of Stephanocrinus . Journal of Paleontology 57, 627–51.Google Scholar
Brett, C. E., Goodman, W. M. & LoDuca, S. T. 1990. Sequences, cycles, and basin dynamics in the Silurian of the Appalachian Foreland Basin. Sedimentary Geology 69, 191–244.Google Scholar
Brett, C. E. & Liddell, W. D. 1978. Preservation and paleoecology of a Middle Ordovician hardground community. Paleobiology 3, 329–48.Google Scholar
Brett, C. E., Moffat, H. A. & Taylor, W. L. 1997. Echinoderm taphonomy, taphofacies, and Lagerstätten. In Geobiology of Echinoderms (eds Maples, C. G. & Waters, J. A.), pp. 147–90. Paleontological Society Papers 3.Google Scholar
Brett, C. E. & Ray, D. C. 2005. Sequence and event stratigraphy of Silurian strata of the Cincinnati Arch region: correlations with New York-Ontario successions. Proceedings of the Royal Society of Victoria 117, 175–98.Google Scholar
Briggs, D. E. G. 2003. The role of decay and mineralization in the preservation of soft-bodied fossils. Annual Review of Earth and Planetary Sciences 31, 275–301.Google Scholar
Broadhead, T. W. 1980. Blastozoa. In Echinoderms: Notes for a Short Course (eds Broadhead, T. W. & Waters, J. A.), pp. 118–32. University of Tennessee Studies in Geology 3.Google Scholar
Bromley, R. G. 1975. Trace fossils at omission surfaces. In The Study of Trace Fossils (ed. Frey, R. W.), pp. 399–428. Berlin: Springer-Verlag.Google Scholar
Canfield, D. E. & Raiswell, R. 1991. Pyrite formation and fossil preservation. In Taphonomy: Releasing the Data Locked in the Fossil Record (eds Allison, P. A. & Briggs, D. E. G.), pp. 337–87. New York: Plenum Press.Google Scholar
Cherns, L., Wheeley, J. R. & Caris, L. 2006. Tunneling trilobites: habitual infaunalism in an Ordovician carbonate seafloor. Geology 34, 657–60.Google Scholar
Conkin, J. E. 2003. Podolithus Sardeson, 1908, crinoid holdfast morphogenus, revised, and its use in recognition of paracontinuities in lower Paleozoic. University of Louisville Studies in Paleontology and Stratigraphy 25, 1–27.Google Scholar
Connell, J. H. 1976. Competitive interactions and the species diversity of corals. In Coelenterate Ecology and Behavior (ed. Mackie, G. O.), pp. 51–8. New York: Plenum Press.Google Scholar
Cornell, S. R., Brett, C. E. & Sumrall, C. D. 2003. Paleoecology and taphonomy of an edrioasteroid-dominated hardground association from tentaculitid limestones in the Early Devonian of New York: a Paleozoic rocky peritidal community. Palaios 18: 212–24.Google Scholar
Dayton, P. K. 1971. Competition, disturbance, and community organization: the provision and subsequent utilization of space in a rocky intertidal community. Ecological Monographs 41, 351–89.Google Scholar
Donovan, S. K. 1991. The taphonomy of echinoderms: calcareous multi-element skeletons in the marine environment. In The Processes of Fossilization (ed. Donovan, S. K.), pp. 241–69. New York: Columbia University Press.Google Scholar
Donovan, S. K. & Harper, D. A. T. 2010. Nurse logs and nurse crinoids? A palaeobotanical concept applied to fossil crinoids. Lethaia 43, 591–2.Google Scholar
Donovan, S. K., Harper, D. A. T. & Håkansson, E. 2007. The root of the problem: palaeoecology of distinctive attachment structures from the Silurian (Wenlock) of Gotland. Lethaia 40, 313–20.Google Scholar
Donovan, S. K. & Lewis, D. N. 2010. Aspects of crinoid palaeontology, Much Wenlock Limestone Formation, Wenlock Edge, Shropshire (Silurian). Proceedings of the Yorkshire Geological Society 58, 9–14.Google Scholar
Donovan, S. K. & Pickerill, R. K. 2002. Pattern versus process or informative versus uninformative ichnotaxonomy: reply to Todd and Palmer. Ichnos 9, 85–7.Google Scholar
Eckert, J. D. 1988. The ichnogenus Tremichnus in the Lower Silurian of western New York. Lethaia 21, 281–3.Google Scholar
Ettensohn, F. R. 1978. Acrothoracic barnacle borings from the Chesterian of eastern Kentucky and Alabama. Southeastern Geology 20, 27–31.Google Scholar
Foerste, A. F. 1897. A report on the Middle and Upper Silurian rocks of Clark, Jefferson, Ripley, Jennings, and southern Decatur Counties, Indiana. Indiana Department of Geology and Natural Resources Annual Report 21, 213–88.Google Scholar
Foerste, A. F. 1898. A report on the Niagara limestone quarries of Decatur, Franklin, and Fayette Counties, with remarks on the geology of the Middle and Upper Silurian rocks of these and neighboring (Ripley, Jennings, Bartholomew, and Shelby) Counties. Indiana Geological Survey Annual Report 22, 193–225.Google Scholar
Franzén, C. 1977. Crinoid holdfasts from the Silurian of Gotland. Lethaia 10, 219–34.Google Scholar
Franzén-Bengtson, C. 1983. Radial perforations in crinoid stems from the Silurian of Gotland. Lethaia 16, 291–302.Google Scholar
Frest, T. J. 1975. Caryocrinitidae (Echinodermata: Rhombifera) of the Laurel Limestone of southeastern Indiana. Fieldiana: Geology 30, 81–106.Google Scholar
Frest, T. J., Brett, C. E. & Witzke, B. J. 1999. Caradocian to Gedinnian echinoderm associations of central and eastern North America. In Paleocommunities: A Case Study from the Silurian and Lower Devonian (eds Boucot, A. J. & Lawson, J. D.), pp. 638–783. Cambridge: Cambridge University Press.Google Scholar
Frest, T. J., Mikulic, D. G. & Paul, C. R. C. 1977. New information on the Holocystites fauna (Diploporita) of the middle Silurian of Wisconsin, Illinois, and Indiana. Fieldiana: Geology 35, 83–108.Google Scholar
Frest, T. J., Strimple, H. L. & Paul, C. R. C. 2011. The North American Holocystites fauna (Echinodermata, Blastozoa: Diploporita): paleobiology and systematics. Bulletins of American Paleontology 380, 1–141.Google Scholar
Gil Cid, M. D. & Domínguez-Alonso, P. 2000. Attachment strategies in Diploporita inhabiting soft-substratum communities. In Echinoderms 2000 (ed. Barker, M.), pp. 83–6. Rotterdam: A. A. Balkema.Google Scholar
Glass, A. 2006. Pyritized tube-feet in a protasterid ophiuroid from the Upper Ordovician of Kentucky, U.S.A. Acta Palaeontologica Polonica 51, 171–84.Google Scholar
Glass, A. & Blake, D. B. 2004. Preservation of tube feet in an ophiuroid (Echinodermata) from the Lower Devonian Hunsrück Slate of Germany and a redescription of Bundenbachia benecki and Palaeophiomyxa grandis . Paläontologische Zeitschrift 78, 73–95.Google Scholar
Halleck, M. S. 1973. Crinoids, hardgrounds, and community succession: the Silurian Laurel-Waldron contact in southern Indiana. Lethaia 6, 239–51.Google Scholar
Hudson, J. D. 1982. Pyrite in ammonite-bearing shales from the Jurassic of England and Germany. Sedimentology 25, 339–69.Google Scholar
Jackson, J. B. C. 1977. Competition on marine hard substrata: the adaptive significance of solitary and colonial strategies. American Naturalist 111, 743–67.Google Scholar
Jackson, J. B. C. 1979. Overgrowth competition between encrusting cheilostome ectoprocts in a Jamaican cryptic reef environment. Journal of Animal Ecology 48, 805–23.Google Scholar
Jackson, J. B. C. & Buss, L. 1975. Allelopathy and spatial competition among coral reef invertebrates. Proceedings of the National Academy of Science 72, 5160–3.Google Scholar
Jackson, J. B. C., Goreau, T. F. & Hartman, W. D. 1971. Recent brachiopod-coralline sponge communities and their paleoecological significance. Science 173, 623–5.Google Scholar
Kammer, T. K. & Ausich, W. I. 2007. Soft-tissue preservation of the hind gut in a new genus of cladid crinoid from the Mississippian (Visean, Asbian) at St Andrews, Scotland. Palaeontology 50, 951–9.Google Scholar
Kidwell, S. M. 1993. Patterns of time-averaging in the shallow marine fossil record. In Taphonomic Approaches to Time Resolution in Fossil Assemblages (eds Kidwell, S. M. & Behrensmeyer, A. K.), pp. 275–300. Paleontological Society Short Courses in Paleontology 6.Google Scholar
Kindle, E. M. & Barnett, V. H. 1909. The stratigraphic and faunal relations of the Waldron fauna in southern Indiana. Indiana Geological Survey Annual Report 23, 393–415.Google Scholar
Kleffner, M. A., Cramer, B. D., Brett, C. E., Mikulic, D. G., Kluessendorf, J. & Johnson, T. 2012. Lower Silurian of western Ohio—The case of the disappearing Dayton, and unique Midwestern co-occurrence of pentamerid brachiopods with the Gravicalymene celebra Trilobite Association in the Springfield Formation. In On and Around the Cincinnati Arch and Niagara Escarpment: Geological Field Trips in Ohio and Kentucky for the GSA North-Central Section Meeting, Dayton, Ohio, 2012 (eds Sandy, M. R. & Goldman, D.), pp. 1–18. Geological Society of America Field Guide 27.Google Scholar
Kolbe, S. E., Zambito, J. J. IV, Brett, C. E., Wise, J. L. & Wilson, R. D. 2011. Brachiopod shell discoloration as an indicator of taphonomic alteration in the deep-time fossil record. Palaios 26, 682–92.Google Scholar
Lewis, R. D. 1980. Taphonomy. In Echinoderms: Notes for a Short Course (eds Broadhead, T. W. & Waters, J. A.), pp. 27–39. University of Tennessee Studies in Geology 3.Google Scholar
Lewis, R. D. 1982. Holdfasts. In Echinoderm Faunas from the Bromide Formation (Middle Ordovician) of Oklahoma (ed. Sprinkle, J.), pp. 57–64. University of Kansas Paleontological Contributions Monograph 1.Google Scholar
McKinney, F. K. 1995. Taphonomic effects and preserved overgrowth relationships among encrusting marine organisms. Palaios 10, 279–82.Google Scholar
McLaughlin, P. I., Brett, C. E. & Wilson, M. A. 2008. Hierarchy of sedimentary discontinuity surfaces and condensed beds from the middle Paleozoic of eastern North America: implications for cratonic sequence stratigraphy. In Dynamics of Eperic Seas (eds Pratt, B. & Holmden, C.), pp. 175–200. Geological Association of Canada Special Paper 48.Google Scholar
McLaughlin, P. I., Cramer, B. D., Brett, C. E. & Kleffner, M. A. 2008. Silurian high-resolution stratigraphy on the Cincinnati Arch: progress on recalibrating the layer-cake. In From the Cincinnati Arch to the Illinois Basin: Geological Field Excursions along the Ohio River Valley (eds Maria, A. H. & Counts, R. C.), pp. 119–80. Geological Society of America Field Guide 12.Google Scholar
McLaughlin, P. I., Emsbo, P. & Brett, C. E. 2012. Beyond black shales: the sedimentary and stable isotope records of oceanic anoxic events in a predominantly oxic basin (Silurian; Appalachian Basin, USA). Palaeogeography, Palaeoclimatology, Palaeoecology 367–368, 153–77.Google Scholar
McNamara, M. E., Orr, P. J., Kearns, S. L., Alcalá, L., Anadón, P. & Mollá, E. P. 2009. Soft-tissue preservation in Miocene frogs from Libros, Spain: insights into the genesis of decay microenvironments. Palaios 24, 104–17.Google Scholar
Meyer, D. L. 1990. Population paleoecology and comparative taphonomy of two edrioasteroid (Echinodermata) pavements: Upper Ordovician of Kentucky and Ohio. Historical Biology 4, 155–78.CrossRefGoogle Scholar
Moore, R. C., Jeffords, R. M. & Miller, T. H. 1968. Morphological features of crinoid columns. University of Kansas Paleontological Contributions, Echinodermata 8, 1–30.Google Scholar
Nebelsick, J. H. 2004. Taphonomy of echinoderms: introduction and outlook. In Echinoderms: München (eds Heinzeller, T. & Nebelsick, J. H.), pp. 471–7. London: Taylor and Francis Press.Google Scholar
Niedźwiedzki, R., Salamon, M. A. & Wolkenstein, K. 2011. Encrinus aculeatus (Crinoidea: Encrinida) with exceptional preservation of organic pigments from the Middle Triassic of Lower Silesia (SW Poland). Neues Jahrbuch für Geologie und Palaontologie Abhalunden 262, 163–70.Google Scholar
O'Malley, C. E., Ausich, W. I. & Chin, Y.-P. 2008. Crinoid biomarkers (Borden Group, Mississippian): implications for phylogeny. In Echinoderm Paleobiology (eds Ausich, W. I. & Webster, G. D.), pp. 290–306. Bloomington: Indiana University Press.Google Scholar
O'Malley, C. E., Ausich, W. I. & Chin, Y.-P. 2013. Isolation and characterization of the earliest taxon-specific organic molecules (Mississippian, Crinoidea). Geology 41, 347–50.Google Scholar
Palmer, T. J. & Palmer, C. D. 1977. Faunal distribution and colonization strategy in a Middle Ordovician hardground community. Lethaia 10, 179–200.Google Scholar
Paul, C. R. C. 1971. Revision of the Holocystites fauna (Diploporita) of North America. Fieldiana: Geology 24, 1–166.Google Scholar
Paul, C. R. C. 1973. British Ordovician cystoids, part 1. Palaeontographical Society Monographs 127, 1–64.Google Scholar
Paul, C. R. C. & Bockelie, J. F. 1983. Evolution and functional morphology of the cystoid Sphaeronites in Britain and Scandinavia. Palaeontology 26, 687–734.Google Scholar
Pickerill, R. K. & Donovan, S. K. 1998. Ichnology of the Pliocene Bowden shell bed, southeast Jamaica. Contributions to Tertiary and Quaternary Geology 35, 161–75.Google Scholar
Pinsak, A. P. & Shaver, R. H. 1964. The Silurian formations of northern Indiana. Indiana Geological Survey Bulletin 32, 1–87.Google Scholar
Radtke, G., Hofmann, K. & Golubic, S. 1997. A bibliographic overview of micro- and macroscopic bioerosion. Courier Forschungsinstitut Senckenberg 210, 307–40.Google Scholar
Rodda, P. U. & Fisher, W. L. 1962. Upper Paleozoic acrothoracic barnacles from Texas. Texas Journal of Science 14, 460–79.Google Scholar
Seilacher, A. 1973. Biostratinomy: the sedimentology of biologically standardized particles. In Evolving Concepts in Sedimentology (ed. Ginsburg, R. N.), pp. 159–77. Baltimore: Johns Hopkins University Press.Google Scholar
Seilacher, A. & MacClintock, C. 2005. Crinoid anchoring strategies for soft-bottom dwelling. Palaios 20, 224–40.Google Scholar
Sprinkle, J. & Rodgers, J. C. 2010. Competition between a Pennsylvanian (Late Carboniferous) edrioasteroid and a bryozoan for living space on a brachiopod. Journal of Paleontology 84, 356–9.Google Scholar
Sumrall, C. D., Sprinkle, J. & Bonem, R. A. 2006. An edrioasteroid-dominated echinoderm assemblage from a Lower Pennsylvanian marine conglomerate in Oklahoma. Journal of Paleontology 80, 229–44.Google Scholar
Taylor, P. D. & Wilson, M. A. 2003. Palaeoecology and evolution of marine hard substrate communities. Earth-Science Reviews 62, 1–103.Google Scholar
Thomka, J. R. & Brett, C. E. 2013. Substrate-controlled variability within attachment structures of Caryocrinites (Echinodermata: Rhombifera) from the middle Silurian of southeastern Indiana. Geological Society of America Abstracts with Programs, North-Central Section 46, 11.Google Scholar
Thomka, J. R. & Brett, C. E. In press. Diploporite (Echinodermata: Blastozoa) thecal attachment structures from the Silurian of southeastern Indiana. Journal of Paleontology 87.Google Scholar
Thomka, J. R. & Lewis, R. D. In press. Siderite concretions in the Copan crinoid Lagerstätte (Upper Pennsylvanian, Oklahoma): Implications for interpreting taphonomic and depositional processes in mudstone successions. Palaios 28.Google Scholar
Thomka, J. R., Lewis, R. D., Mosher, D., Pabian, R. K. & Holterhoff, P. F. 2011. Genus-level taphonomic variation within cladid crinoids from the Upper Pennsylvanian Barnsdall Formation, northeastern Oklahoma. Palaios 26, 377–89.Google Scholar
Thomka, J. R., Mosher, D., Lewis, R. D. & Pabian, R. K. 2012. The utility of isolated crinoid ossicles and fragmentary crinoid remains in taphonomic and paleoenvironmental analysis: an example from the Upper Pennsylvanian of Oklahoma, United States. Palaios 27, 465–80.Google Scholar
Walker, K. R. & Bambach, R. K. 1971. The significance of fossil assemblages from fine-grained sediments: time-averaged communities. Geological Society of America Abstracts with Programs 3, 783–4.Google Scholar
Warme, J. E. 1975. Borings as trace fossils, and the processes of marine bioerosion. In The Study of Trace Fossils (ed. Frey, R. W.), pp. 181–227. Berlin: Springer-Verlag Press.Google Scholar
Widdison, R. E. 2001. Symbiosis in crinoids from the Wenlock of Britain. In Echinoderms 2000 (ed. Barker, M.), pp. 139–43. Rotterdam: A. A. Balkema.Google Scholar
Wilson, M. A. & Palmer, T. E. 1992. Hardgrounds and Hardground Faunas. University of Wales, Aberystwyth, Institute of Earth Studies Publications 9.Google Scholar
Wolkenstein, K., Głuchowski, E., Gross, J. H. & Marynowski, L. 2008. Hypericinoid pigments in millericrinids from the lower Kimmeridgian of the Holy Cross Mountains (Poland). Palaios 23, 773–7.Google Scholar
Wolkenstein, K., Gross, J. H., Heinz, F. & Schöler, H. F. 2006. Preservation of hypericin and related polycyclic quinone pigments in fossil crinoids. Proceedings of the Royal Society of London 273, 451–6.Google Scholar
Zamora, S., Clausen, S., Álvaro, J. J. & Smith, A. B. 2010. Pelmatozoan echinoderms as colonizers of carbonate firmgrounds in mid-Cambrian high energy environments. Palaios 25, 764–8.Google Scholar