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Distinguishing Earth’s oldest known bryozoan (Pywackia, late Cambrian) from pennatulacean octocorals (Mesozoic–Recent)

Published online by Cambridge University Press:  04 June 2015

Ed Landing
Affiliation:
New York State Museum, 222 Madison Avenue, Albany, NY 12230, and Department of Earth and Environmental Sciences and Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, 10964, USA, 〈[email protected]
Jonathan B. Antcliffe
Affiliation:
Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, United Kingdom, 〈[email protected]
Martin D. Brasier
Affiliation:
Department of Earth Sciences, Oxford University, South Parks Road, Oxford OX1 3AN, United Kingdom
Adam B. English
Affiliation:
Chevron, 1400 Smith Street, Suite 12-161, Houston, TX 77002, USA, 〈[email protected]

Abstract

Bryozoans and all biomineralized metazoan phyla extend back into the Cambrian. Pywackia Landing, 2010 is confirmed as a secondarily phosphatized, late Cambrian stenolaemate bryozoan with colonial habit; mineralized zooarium (originally calcareous); granular/rarely granular-prismatic histology of its trilamellar walls; and polymorphism shown by deep autozooecia with diaphragms and hemiphragms, axial zooecia with diaphragms, and probable nanozooecia. The irregular form of Pywackia reflects growth as a 14-hedron that could not branch and a lack of structures such as thickened walls or styles that maintain regular autozooecial spacing in later stenolaemates. Pywackia is a stem group stenolaemate with a stolon modified into a budding axial zooid and autozooid budding. It is morphologically simpler than the highly evolved late Tremadocian bryozoans of South China with features such as styles, cystiphragms, thickened zooecial walls, and massive or branching colonies. As with some bryozoans, Pywackia lacks holdfasts but has lineated living chambers and variably sized autozooecia. The late Cambrian origin of bryozoans, euconodonts, polyplacophorans, and cephalopods set the stage for the Ordovician Radiation’s complex communities. Pywackia is not a pennatulacean octocoral. It lacks both a pennatulacean axial rod histology and a budding zooid that remains confluent with daughter autozooids. Indeed, Pywackia walled off its axial zooid. Similarity of the 6- and 12-sided Pywackia zooarium with circular to 4-sided pennatulacean axes only includes calcareous composition and the general shapes of Pywackia zooaria and some Lituaria axial rods. The pennatulacean record does not extend from the Mesozoic into the Cambrian, and early cnidarians were not phosphatic. The diagnosis of Pywackia is modified.

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Articles
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Copyright © 2015, The Paleontological Society 

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Footnotes

Deceased 16 December 2014

References

Antcliffe, J.B., and Brasier, M.D., 2007, Charnia and sea pens are poles apart: Journal of the Geological Society of London, v. 164, p. 4951, doi: 10.1144/0016-76492006-080.Google Scholar
Antcliffe, J.B., and Brasier, M.D., 2008, Charnia at 50: developmental models for Ediacaran fronds: Palaeontology, v. 51, p. 1126, doi: 10.1111/j.1475-4983.2007.00738.x.Google Scholar
Astrova, G.G., 1964, Novyi otryad paleozoiskikh mshanok: Paleontologicheskii Zhurnal, v. 1964, no. 3, 2231.Google Scholar
Ausich, W.I., and Babcock, L.C., 1998, The phylogenetic position of Echmatocrinus brachiatus, a probable octocoral from the Burgess Shale: Palaeontology, v. 41, p. 193202.Google Scholar
Balss, H., 1910, Japanische Pennatuliden. Abhandlungen Mathematische-physich. Klasse Akademie Wissenschaften, Suppl. 1, no. 10, 106 p.Google Scholar
Bassler, R.S., 1952, Taxonomic notes on genera of fossil and Recent Bryozoa: Journal of the Washington Academy of Sciences, v. 42, p. 381385.Google Scholar
Bassler, R.S., 1953, Part G. Bryozoa, in R. C. Moore, ed., Treatise on Invertebrate Paleontology. Part G. Bryozoa: Geological Society of America and University of Kansas Press, 253 p.Google Scholar
Bayer, F.M., 1955, Contributions to the nomenclature, systematics, and morphology of the Octocorallia: Proceedings of the U. S. National Museum, v. 105, p. 207220.CrossRefGoogle Scholar
Bayer, F.M., 1956, Octocorallia, in R. C. Moore, ed., Treatise on Invertebrate Paleontology, Part F. Coelenterata: Geological Society of America and University of Kansas Press, p. 166231.Google Scholar
Bayer, F.M., 1973, Colonial organization in octocorals, in Boardman, R.S., Cheetham, A.H., and Oliver, W.A., eds., Animal Colonies: Stroudsburg, Pennsylvania, Dowden, Hutchinson & Ross, Inc., p. 6993.Google Scholar
Bengtson, S., 1968, The problematic genus Mobergella from the Lower Cambrian of the Baltic area: Lethaia, v. 1, p. 325351, doi: 10.1111/j.1502-3931.1968.tb01625.x.CrossRefGoogle Scholar
Bengtson, S., 1981, Atractosella, a Silurian ancynacean octocoral: Journal of Paleontology, v. 55, p. 281–194.Google Scholar
Bengtson, S., Morris, S.C., Cooper, B.J., Jell, P.A., and Runnegar, B.N., 1990, Early Cambrian fossils from South Australia: Memoirs of the Association of Australasian Palaeontologists, v. 9, 364 p.Google Scholar
Blake, D.B., 1976, Functional morphology and taxonomy of branch dimorphism in the Paleozoic bryozoan genus Rhabdomeson: Lethaia, v. 9, p. 169178, doi: 10.1111/j.1502-3931.1976.tb00964.x.CrossRefGoogle Scholar
Blake, D.B., 1983a, The order Cryptostomata, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 440452.Google Scholar
Blake, D.B., 1983b, Systematic descriptions for the suborder Rhabdomesina, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 550592.Google Scholar
Boardman, R.S., 1971, Mode of growth and functional morphology of autozooids in some Recent and Paleozoic tubular Bryozoa: Smithsonian Contributions in Paleobiology, v. 6, 51 p.Google Scholar
Boardman, R.S., 1983, General features of the Class Stenolaemata, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. G48G137.Google Scholar
Boardman, R.S., and Cheetham, A.H., 1983, Glossary of morphological terms, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 304326.Google Scholar
Boardman, R.S., and Cheetham, A.H., 1987, Phylum Bryozoa, in Boardman, R.S., Cheetham, A.H., and Rowell, A.J., eds., Fossil Invertebrates: Oxford, Blackwell Scientific Publications, p. 497549.Google Scholar
Boardman, R.S., McKinney, F.K., and Taylor, P.D., 1992, Morphology, anatomy, and systematicvs of the Cinctiporidae, new family (Bryozoa: Stenolemata): Smithsonian Contributions to Paleobiology, v. 70, 81 p.Google Scholar
Borg, F., 1926, Studies on Recent cyclostomatous Bryozoa: Zoologiska bidrag från Uppsala, v. 10, p. 181507.Google Scholar
Brasier, M.D., 1990, Phosphogenic events and skeletal preservation across the Precambrian–Cambrian boundary interval, in Notholt, A.G., and Jarvis, I., eds., Phosphorite research and development: Special Publication of the Geological Society of London, 52, p. 289303.Google Scholar
Brasier, M.D., 1992, Palaeoceanography and changes in the biological cycling of phosphorus across the Precambrian-Cambrian boundary, in Lipps, J., and Signor, P.W., eds., Origins of the Metazoa: New York, Plenum Press, p. 483523.Google Scholar
Brasier, M.D., and Hewitt, R.A., 1979, Environmental setting of fossiliferous rocks from the uppermost Proterozoic–Lower Cambrian of central England: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 27, p. 3557, doi:10.1016/0031-0182(79)90092-0.CrossRefGoogle Scholar
Cheetham, A.H., and Cook, P.L., 1983, General features of the class Gymnolaemata, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised. Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 138207.Google Scholar
Conway Morris, S., 1993, The fossil record and the early evolution of the Metazoa: Nature, v. 361, 219225, doi:10.1038/361219a0.CrossRefGoogle Scholar
Cook, P.L., 1979, Mode of life of small, rooted “sand fauna” colonies, in Larwood, G.P., and Abbott, M.D., eds., Advances in Bryozoology: Academic Press, London, p. 269282.Google Scholar
Davidek, K., Landing, E., Bowring, S.A., Westrop, S.R., Rushton, A.W.A., Fortey, R.A., and Adrain, J.M., 1998, New uppermost Cambrian U-Pb date from Avalonian Wales and age of the Cambrian–Ordovician boundary: Geological Magazine, v. 135, p. 305309.Google Scholar
de Koninck, L.G., 1876, Recherchés sur les fossils paléozïques de la Nouvelle-Galles (Australie): Mémoires de la Societé Royale des Sciences de Liége, 20th series, v. 6, 235 p.Google Scholar
d’Hondt, M.-J., 1984, Contribution à la connaisissance de certains genres de la famille Veretillidae (Pennatulacea). Description de Cavernulina grandiflora n. sp. et de Lituaria valenciennesi nom. nov. Bulletin de l’Museum Nationale de Historie Naturella, Paris, 4th series, v. 6, p. 625640.Google Scholar
Dolan, E., Tyler, P.A., Yesson, C., and Rogers, A.D., 2013, Phylogeny and systematics of deep-sea sea pens (Anthozoa: Octocorallia: Pennatulacea): Molecular Phylogenetics and Evolution, v. 69, p. 610618, doi:10.1016/j.ympev.2013.07.018.Google Scholar
Dzik, J., 1991, Possible solitary bryozoan ancestors from the early Palaeozoic and affinities of the Tentaculitida, in Bigey, F.P., ed., Bryozoaires Actuels et Fossils. Bulletin de l’Societé des Sciences Naturelles de l’Ouest de France, Memoir 1: France, Nantes, p. 121131.Google Scholar
Dzik, J., 1992, Early astrogeny and relationships of the Ordovician rhabdomesine bryozoans: Acta Palaeontologica Polonica, v. 37, p. 3754.Google Scholar
Dzik, J., 2002, Possible ctenophoran affinities of the Precambrian “sea pen” Rangea: Journal of Morphology, v. 252, p. 315324, doi: 10.1002/jmor.1108.Google Scholar
Ehrenberg, G.C., 1831, Symbolae physicae seu icons et descriptions corporum naturalium, Zoologica 4, Animalia evertebrata exclusis insectis: Berolini, 428 p.Google Scholar
Ernst, A., and Carrera, M., 2012, Upper Ordovician (Sandbian) bryozoan fauna from the Argentine Precordilera: Journal of Paleontology, v. 86, p. 721752.CrossRefGoogle Scholar
Federov, P.V., Krusanov, V., and Federov, P.V., 1997, Phosphatized remains of bryozoans from deposits of the Volkov Formation (Lower Ordovician, Arenig) in the St. Petersburg region: All Russian and International Conference on Bryozoa (1997) – Abstracts, www.bryozoa.net/russabst.html.Google Scholar
Franc, S.A.H., and Chassagne, G., 1974, Ètude untrastructurale et physico-chimique de l’axe squelettique de Veretillium cynomorium Pall, (Cnidare, Anthozoaïre): cellules, calcite, collagène: Journal de Microscopie, v. 21, p. 93101.Google Scholar
Frech, F., 1890, Die Korallenfauna der Trias, 1, Die Korallen der juvavschen Triasprovinz: Palaeontographica, v. 37, 116 p.Google Scholar
Gray, J.E., 1859, Arrangement of zoophytes with pinnated tentacles: Annuals and Magazine of Natural History, v. 1858, p. 430.Google Scholar
Haeckel, E., 1866, Generelle Morphologie der Organismen. Allgemeine Grundzüge der organischen Formen-Wissenschaft, Mechanischbegründel Durch die von Charles Darwin Reformirke Descendentheorie: Berlin, Georg Reiner, v. 1, 574 p.Google Scholar
Hageman, S. J., Bock, P. E., Bone, Y., and McGowran, B., 1998, Bryozoan growth habits: Classification and analysis: Journal of Paleontology, v. 72, p. 418436.Google Scholar
Hageman, S.J., James, N.P., and Bone, Y., 2000, Cool-water carbonate production from epizoic bryozoans on ephemeral substrates: Palaios, v. 15, p. 3348.Google Scholar
Hall, J., 1847, Palaeontology of New York, Albany, van Benthusen, v. 1, 338 p.Google Scholar
Hall, J., 1881, (issued in 1883), Bryozoans of the upper Helderberg and Hamilton groups: Transactions of the Albany Institute, v. 10, 36 p.Google Scholar
Hall, J., 1886, Bryozoa of the upper Helderberg Group; plates and explanation: Report of the New York State Geologist, 5th Annual Report for 1885, p. 25–53.Google Scholar
Hall, J., and Simpson, G.B., 1887, Corals and Bryozoa. Descriptions and figures of species from the lower Helderberg, upper Helderberg, and Hamilton Groups: Palaeontology of New York, v. 6, 298 p.Google Scholar
Herklots, J.A., 1858, Notices pour server à l’etude de Polypiers nageurs ou pennitulides: Amsterdam Bijdragen tot de Dierkunde, v. 7, p. 130.Google Scholar
Hutton, F.W., 1873. Catalogue of the Marine Mollusca of New Zealand, with Diagnoses of the Species: Colonial Museum and Geological Survey Department, Wellington, New Zealand, 116 p.Google Scholar
Karklins, O.L., 1983, Introduction to the suborder Ptilodictyina, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised. Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 451488.Google Scholar
Koch, G., 1878, Notiz über die Zooide von Pennatula: Zoologischer Anzeiger, v. 1, p. 103104.Google Scholar
Kölliker, A.V., 1880, Report on the Pennatulida dredged by HMS Challenger during the years 1873–1876, Report of the Scientific Results of the Voyage of the HMS Challenger during the years 1873–1876: Zoology, v. 11, p. 141.Google Scholar
Kouchinsky, A., Bengtson, S., Runnegar, B.N., Skovsted, C., Steiner, M., and Vendrasco, M., 2012, Chronology of Early Cambrian biomineralization: Geological Magazine, v. 149, p. 221251, doi: 10.1017/S0016756811000720.Google Scholar
Kükenthal, W., 1915, Ordo Pennatularia: Das Tierreich, v. 43, p. 1132 p.Google Scholar
Lamouroux, A.V.F., 1816. Historie des Polypiers Coralligènes Flexiniles, Vulgairement Nommés Zoophytes: Caen, Impr. de F. Poisson, 559 p.Google Scholar
Landing, E., 1984, Skeleton of lapworthellids and the suprageneric classification of tommotiids (Early and Middle Cambrian phosphatic problematica): Journal of Paleontology, v. 58, p. 13801398.Google Scholar
Landing, E., 1992, Lower Cambrian of southeastern Newfoundland: Epeirogeny and Lazarus faunas, lithofacies-biofacies linkages, and the myth of a global chronostratigraphy, in Lipps, J., and Signor, P.W., eds., Origins and Early Evolution of Metazoa: New York, Plenum Press, p. 283309.Google Scholar
Landing, E., 1996, Avalon—insular continent by the latest Precambrian, in Nance, R.D., and Thompson, M., eds., Avalonian and related peri-Gondwanan terranes of the circum-North Atlantic: Geological Society of America Special Paper 304, p. 2764.Google Scholar
Landing, E., Bowring, S.A., Davidek, K., Rushton, A.W.A., Fortey, R.A., and Wimbledon, W.A.P., 2000, Cambrian–Ordovician boundary age and duration of the lowest Ordovician Tremadoc Series based on U-Pb zircon dates from Avalonian Wales: Geological Magazine, v. 137, p. 485494.Google Scholar
Landing, E., Bowring, S.A., Fortey, R.A., and Davidek, K., 1997, U-Pb zircon date from Avalonian Cape Breton Island and geochronologic calibration of the Early Ordovician: Canadian Journal of Earth Sciences, v. 34, p. 724730, doi: 10.1139/e17-059.Google Scholar
Landing, E., English, A., and Keppie, J.D., 2010, Cambrian origin of all skeletalized metazoan phyla—discovery of Earth’s oldest bryozoans (Upper Cambrian, southern Mexico): Geology, v. 38, p. 547550, doi: 10.1130/G30870.1.Google Scholar
Landing, E., Geyer, G., Brasier, M.D., and Bowring, S.A., 2013a, Cambrian Evolutionary Radiation: context, correlations, and chronostratigraphy—overcoming deficiencies of the first appearance datum (FAD) concept: Earth-Science Reviews, v. 123, p. 133177, doi:10.10.1016/jearscirev.2013.008.Google Scholar
Landing, E., Keppie, J.D., and Westrop, S.R., 2006a, Lower Paleozoic of northwest Gondwana—Terminal Cambrian–lowest Ordovician Tiñu Formation of Oaxaca, southern Mexico: Geological Society of America, Abstracts with Programs, v. 38, no. 2, p. 21.Google Scholar
Landing, E., Myrow, P., Benus, A.P., and Narbonne, G.M., 1989, The Placentian Series: appearance of the oldest skeletalized faunas in southeastern Newfoundland: Journal of Paleontology, v. 63, p. 739769.Google Scholar
Landing, E., Peng, S.C., Babcock, L.E., Geyer, G., and Moczydłowska-Vidal, M., 2007b, Global standard names for the lowermost Cambrian series and stage: Episodes, v. 30, p. 287289.Google Scholar
Landing, E., and Westrop, S.R., 2004, Environmental patterns in the origin and evolution and diversification loci of Early Cambrian skeletalized Metazoa: evidence from the Avalon microcontinent, in Lipps, J.H., and Wagoner, B., eds., Neoproterozoic–Cambrian Biological Revolutions: Paleontological Society Papers, v 10, p. 93105.Google Scholar
Landing, E., Westrop, S.R., and Bowring, S.A., 2013b, Reconstructing the Avalonia palaeocontinent in the Cambrian: a 519 Ma caliche in South Wales and transcontinental middle Terreneuvian Epoch sandstones: Geological Magazine, v. 150, p. 10221046, doi:10.1017/S00167681300228.Google Scholar
Landing, E., Westrop, S.R., and Keppie, J.D., 2006b, Cambrian–Ordovician boundary interval in Mexican northwest Gondwana—The Tiñu Formation of Oaxaca State, in Jago, J.B., ed., XI International Conference of the Cambrian Stage Subcommission Working Group, South Australia, August 14–24, 2006, Geological Society of Australia, Abstracts, no. 84, p. 18.Google Scholar
Landing, E., Westrop, S.R., and Keppie, J.D., 2007a, Terminal Cambrian and lowest Ordovician succession of Mexican West Gondwana—biotas and sequence stratigraphy of the Tiñu Formation: Geological Magazine, v. 144, p. 909936, doi: 10.1017/S0016756807003585.Google Scholar
Larwood, G.P., and Taylor, P.D., 1979, Early structural and ecological diversification in the Bryozoa, in House, M.R., ed., The Origin of Major Invertebrate Groups, Systematics Association Special Volume No. 12: London, Academic Press, p. 209234.Google Scholar
Ledger, P.W., and Franc, S., 1978, Calcification of the collagenous axial skeleton of Veretillum cynomorium Pall. (Cnidaria, Pennatulacea): Cell and Tissue Research, v. 192, p. 249266.Google Scholar
Lindström, M., 1978, An octocoral from the Lower Ordovician of Sweden: Geologica et Palaeontologica, v. 12, p. 4152.Google Scholar
Lipps, J.H., and Signor, P.W., eds., 1992, Origin and early evolution of the Metazoa: Topics in Geobiology, v. 10, 570 p.Google Scholar
Lutaud, G., 1983, Autozooid morphogenesis in anascan cheilostomates, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 208237.Google Scholar
Ma, J.Y., Taylor, P.D., and Xia, F.S., 2013, New observations on the skeletons of the earliest bryozoans from the Fenhsiang Formation (Tremadocian, Lower Ordovician), Yichang, China: Palaeoworld, v. 23, no. 1, p. 2530, doi: 10.1016/j.palwor.2013.08.002.Google Scholar
Macintyre, I.G., Bayer, F.M., Logan, M.A.V., and Skinner, H.C.W., 2000, Possible vestige of early phosphatic biomineralization in gorgonian octocorals (Coelenterata): Geology, v. 28, p. 455458, doi: 10.1130/0091-7613(2000)28<455:PVOEPB>2.0.CO;2.Google Scholar
McFadden, C., France, S., Sánchez, J.A., and Alderslade, P., 2006, A molecular phylogenetics analysis of the Octocorallia (Cnidaria: Anthozoa) based on mitochondrial protein-coding sequences: Molecular Phylonetics and Evolution, v. 41, p. 513527, doi:10.1016/j.ympev.2006.06.010.CrossRefGoogle ScholarPubMed
McFadden, C., Sánchez, J.A., and France, S., 2010, Molecular phylogenetic insights into the evolution of Octocorallia: A review: Integrative and Comparative Biology, v. 50, p. 389410, doi: 10.1093/icb/icq056.Google Scholar
McKinney, F.K., and Jackson, J.B.C., 1989. Bryozoan Evolution, London, Unwin Hyman, 238 p.Google Scholar
Meinkoth, N.A., 1981. The Audubon Society Field Guide to North American Seashore Creatures: New York, Alfred A. Knopf, 813 p.Google Scholar
Milne-Edwards, H., and Haime, J., 1850, Monographie des polypiers fossils des terraines Palaeozoïques, precede d’un tableau general de la classification des polypes: Archives du Muséum d’historie Naturelle, v. 5, 501 p.Google Scholar
Narbonne, G.M., 2004, Modular construction of early Ediacaran complex life forms: Science, v. 305, p. 11411144, doi: 10.1126/science.1099727.Google Scholar
Narbonne, G.M., Laflamme, M., Greentree, G., and Trusler, P., 2009, Reconstructing a lost world: rangeomorphs from Spaniard’s Bay, Newfoundland: Journal of Paleontology, v. 83, p. 503523.CrossRefGoogle Scholar
Oliver, W.A., and Coates, A.G., 1987, Phylum Cnidaria, in Boardman, R.S., Cheetham, A.H., and Rowell, A.J., eds., Fossil Invertebrates: Oxford,Blackwell Scientific Publications, p. 140193.Google Scholar
Orlov, Y.A., ed. 1962, Fundamentals of Paleontology, Vol. 11, Porifera, Archaeocyatha, Coelenterata, Vermes: Moscow, Izdatel’stvo Akademii Nauk SSSR, 900 p.Google Scholar
Palmer, T.J., and Palmer, C.D., 1977, Fossil distribution and colonization strategy in a Middle Ordovician hardground community: Lethaia, v. 10, p. 179199, doi: 10.1111/j.1502-3931.1977.tb00608.x.Google Scholar
Porter, S.M., 2004, Closing the phosphatization window: testing for the influence of taphonomic bias on the pattern of small shelly fossil decline: Palaios, v. 19, p. 178183, doi: 10.1669/0883-1351(2004)019<0178:CTPWTF>2.0.CO;2.Google Scholar
Reich, M., and Kutscher, M., 2011, Sea pens (Octocorallia: Pennatulacea) from the Late Cretaceous of northern Germany: Journal of Paleontology, v. 85, p. 10421051.Google Scholar
Robison, R.A., and Pantoja-Alor, J., 1968, Tremadocian trilobites from the Nochixtlan region, Oaxaca, Mexico: Journal of Paleontology, v. 42, p. 767800.Google Scholar
Rohwer, S.A., 1910, Some new hymenopterous insects from the Phillipines Islands: Proceedings of the U. S. National Museum, v. 37, p. 657690.Google Scholar
Sandberg, P.A., 1983, Cheilostome and skeletal developments in cheilostome bryozoa, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G Bryozoa Revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. 238286.Google Scholar
Sarichebal, T.G., ed., 1960. Brachiopodi i Foronidi. Osnovyi Paleontologiya Spavochnik: Moscow, Isdatel’stvo Akademiya Nauk CCCP, 324 p.Google Scholar
Schovsbo, N.H., 2001, Why barren intervals? A taphonomic case study of the Scandinavian Alum Shale and its faunas: Lethaia, v. 34, p. 271285, 10.1111/j.1502-3931.2001.tb00056.x.Google Scholar
Shimer, H.W., and Shrock, R.R., 1944. Index Fossils of North America: Massachusetts Institute of Technology, The Technology Press, 837 p.Google Scholar
Simpson, G.B., 1897, A handbook of the genera of the North American Paleozoic Bryozoa; with an introduction upon the structure of living species: 14th Annual Report of the New York State Geological Survey (for 1885), p. 403–669.Google Scholar
Sober, E., 1988. Reconstructing the Past, Parsimony, Evolution, and Inference: Cambridge, Massachusetts, The MIT Press, 265 p.Google Scholar
Sprinkle, J., and Collins, D., 1998, Revision of Echmatocrinus from the Middle Cambrian Burgess Shale of British Columbia: Lethaia, v. 31, p. 269282.Google Scholar
Streng, M., Mellbin, B.B., Landing, E., and Keppie, J.D., 2011, Linguliform brachiopods from the terminal Cambrian and lowest Ordovician of the Oaxaquia microcontinent (southern Mexico): Journal of Paleontology, v. 85, p. 122155.Google Scholar
Taylor, P.D., and Ernst, A., 2001, Did bryozoans miss the Cambrian explosion?, in Harper, D.A.T., ed., 45th Annual Meeting of the Palaeontological Society: University of Copenhagen, Geological Museum, p. 15–19.Google Scholar
Taylor, P.D., and Ernst, A., 2004, Bryozoans, in Webby, B.D., Paris, F., Droser, M.L., and Percival, I.G., eds., The Great Ordovician Biodiversification Event: New York, Columbia University Press, p. 147156.Google Scholar
Taylor, M.E., 1966, Precambrian mollusc-like fossils from Inyo County, California: Science, v. 153, p. 198201.Google Scholar
Taylor, P.D., Berning, B., and Wilson, M.A., 2013, Reinterpretation of the Cambrian ‘bryozoan’ Pywackia as an octocoral: Journal of Paleontology, v. 87, p. 984990.Google Scholar
Thompson, D.W., 1917, On Growth and Form: Cambridge University Press, 793 p.Google Scholar
Thompson, J.A., and Simpson, J., 1909. An Account of the Alcyonarians Collected by the Royal Indian Marine Survey Ship “Investigator” in the Indian Ocean. II, The Alcyonarians of the Littoral Area: Calcutta, Trustees of the Indian Museum, 319 p.Google Scholar
Tiegler, D.J., and Towe, K.M., 1975, Microstructure and composition of the trilobite skeleton, in Martinsson, A., ed., Evolution and morphology of the Trilobita, Trilobitoidea and Merostomata: Fossils and Strata, 4, p 137149.Google Scholar
Ulrich, E.O., 1888, A list of the Bryozoa of the Waverly Group in Ohio with descriptions of new species: Bulletin of the Scientific Laboratory, Denison University, v. 4, p. 6296.Google Scholar
Ulrich, E.O., 1889. Contributions to micropaleontology of the Cambro-Silurian rocks of Canada Part 2: The Geological and Natural History Survey of Canada, p. 2557.Google Scholar
Ulrich, E.O., 1893, On the Lower Silurian Bryozoa of Minnesota: The Geological and Natural History Survey of Minnesota, v. 3, p. 96332.Google Scholar
Utgaard, J., 1983, Systematic descriptions for the order Cystoporata, in Robison, R.A., Ashlock, A., Keim, J., and Williams, R.B., eds., Part G. Bryozoa revised, Treatise on Invertebrate Paleontology: Geological Society of America and University of Kansas Press, p. G440G452.Google Scholar
Verrill, A.E., 1865, Synopsis of the polyps and corals of the North Pacific Exploration Expedition under Commodore C. Ringgold and Captain John Rodgers, U.S.N., from 1853 to 1856, Collected by Dr. Wm. Simpson, naturalist to the expedition with description of some additional species from the west coast of North America: Proceedings of the Essex Institute, Salem, Massachusetts, v. 4, p. 181–194.Google Scholar
Vine, G.R., 1884, Fourth report on the committee appointed for the purpose of reporting on fossil Polyzoa: Report of the 53rd (1883) Meeting of the British Association of Advances in Science, v. 9, p. 161209.Google Scholar
von Hagenow, F., 1851, Der Bryozoen der maastricter Kreidebildung: Cassel, 111 p.Google Scholar
Walford, E.A., 1894, On some Bryozoa from the Inferior Oolite of Shipton Gorge, Dorset: Quarterly Journal of the Geological Society, London, v. 50, p. 7278.Google Scholar
Webby, B.D., 2002, Patterns of Ordovician reef development, in Kiessling, W., Flügel, E., and Golonka, J., eds., Phanerozoic Reef Patterns: SEPM Special Publication 72, p. 129179.Google Scholar
Williams, A., and Rowell, A.J., 1965, Brachiopod anatomy, in Moore, R.C., ed., Treatise on Invertebrate Paleontology, Part H. Brachiopoda, v. 1: Geological Society of America and University of Kansas Press, p. H6H138.Google Scholar
Williams, G.C., 1997, Preliminary assessment of the phylogeny of Pennatulacea (Anthozoa; Octocorallia) with an evaluation of Ediacaran-frond-like fossils, and a synopsis of the history of evolutionary thought regarding the sea pens: Proceedings of the Sixth International Conference on Coelenterate Biology, v. 1995, p. 497509.Google Scholar
Williams, G.C., 2011, The global diversity of sea pens (Cnidaria: Octocorralia: Pennatulacea): PLoS ONE, v. 6, no. 7, e22747, doi: 10.1371/journal.pone.oo22747.Google Scholar
Wilson, M.T., Andrews, A.H., Brown, A.L., and Cordes, E.E., 2002, Axial rod growth and age estimation of the sea pen, Halipteris willemoesi Kölliker: Hydrobiologia, v. 471, p. 133142, doi: 10.1023/A:1016509506094.Google Scholar
Xia, F., Zhang, S., and Wang, Z., 2007, The oldest bryozoans: new evidence from the late Tremadocian (Early Ordovician) of east Yangtze gorges in China: Journal of Paleontology, v. 81, p. 13081326.Google Scholar
Young, J., and Young, J., 1874, On a new genus of Carboniferous Polyzoa: Annuals and Magazine of Natural History, Series 4, 13, p. 335339.Google Scholar
van der Zee, C., van Raaporst, W., Helder, W., and de Heij, H, 2003, Manganese diagenesis in temporal and permanent depositional areras of the North Sea: Continental shelf research, v. 23, p. 625646, doi:10.1016/S0278-4343(03)00024-4.Google Scholar
Zhuravlev, A.Y., Liñan, E., Vintaned, J.A.G., Debrenne, F., and Fedorov, A.B., 2012, New finds of skeletal fossils in the terminal Neoproterozoic of the Siberian Platform and Spain: Acta Palaeontologica Polonica, v. 57, p. 205224, doi: 10.4202/app.2010.0074.Google Scholar