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The first record of floor plates in pinnules and the earliest record of an anitaxis in rhodocrinitid diplobathrid camerate crinoids

Published online by Cambridge University Press:  22 February 2021

Thomas E. Guensburg Open the ORCID record for Thomas E. Guensburg [Opens in a new window]
Thomas E. Guensburg*
Affiliation:
IRC, Field Museum, 1400 South Lake Shore Drive, Chicago, IL60605
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Abstract

Restudy of Proexenocrinus inyoensis Strimple and McGinnis, 1972, shows that this earliest-known rhodocrinitid diplobathrid camerate crinoid (late Floian, Early Ordovician) expresses the only known record of ambulacral floor plates within pinnules. These pinnule floor plates are remarkably conserved plesiomorphic expressions, with anatomy similar to floor plates of some of the earliest pentaradiate echinoderms, although on a smaller scale. Proexenocrinus floor plates provide direct skeletal evidence that the general resemblance of blastozoan (eocrinoid, diploporan, rhombiferan) brachioles and crinoid pinnules is the product of homoplasy. Proexenocrinus posterior cup morphology is interpreted to include an anitaxis, a distinctive posterior interray morphology.

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Articles
Information
Journal of Paleontology , Volume 95 , Issue 4 , July 2021 , pp. 800 - 804
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Copyright
Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of the The Paleontological Society

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References

Adrain, J.M., McAdams, N.E.B., and Westrop, S.R., 2009, Trilobite biostratigraphy and revised bases of the Tulean and Blackhillsian stages of the Ibexian Series, Lower Ordovician western United States: Memoirs of the Association of Australasian Palaeontologists, v. 37, p. 541–610.Google Scholar
Ausich, W.I., 1986, Crinoids of the Al Rose Formation (Early Ordovician, Inyo County, California, U.S.A.): Alcheringa, v. 10, p. 217–224.CrossRefGoogle Scholar
Ausich, W.I., 1998, Whiterockian (Ordovician) crinoid fauna from the Table Head Group, western Newfoundland, Canada: Canadian Journal of Earth Sciences, v. 35, p. 121–130.CrossRefGoogle Scholar
Ausich, W.I., Kammer, T.W., Rhenberg, E.C., and Wright, D.F., 2015, Early phylogeny of crinoids within the Pelmatozoan clade: Palaeontology, v. 58, p. 937–952.CrossRefGoogle Scholar
Bell, B., and Sprinkle, J., 1978, Totiglobus, an unusual edrioasteroid from the middle Cambrian of Nevada: Journal of Paleontology, v. 52, p. 243–266.Google Scholar
Carpenter, P.H., 1888, Report on the Crinoidea Collected on the Voyage of the H.M.S. Challenger, in the Years 1873–1876, Part II, Comatulae: Report of the Scientific Results of the Voyage of the H.M.S. Challenger, Zoology, v. 26, p. 1–402.Google Scholar
Clark, A.H., 1915, A monograph of the existing crinoids: United States National Museum, Bulletin 82, p. 1–406.Google Scholar
Guensburg, T.E., 2012, Phylogenetic implications of the oldest crinoids: Journal of Paleontology, v. 86, p. 455–461.CrossRefGoogle Scholar
Guensburg, T.E., and Sprinkle, J., 1994, Revised phylogeny and functional interpretation of the Edrioasteroidea based on new taxa from the Early Ordovician of western Utah: Fieldiana (Geology), New Series no. 29, p. 1–43.CrossRefGoogle Scholar
Guensburg, T.E., and Sprinkle, J. 2001, Earliest crinoids: new evidence for the origin of the dominant Paleozoic echinoderms : Geology, v. 29, p. 131–134.2.0.CO;2>CrossRefGoogle Scholar
Guensburg, T.E., and Sprinkle, J., 2003, The oldest known crinoids (Early Ordovician, Utah), and a new crinoid plate homology system: Bulletins of American Paleontology, v. 364, p. 1–43.Google Scholar
Guensburg, T.E., and Sprinkle, J., 2009, Solving the mystery of crinoid ancestry: new fossil evidence of arm origin and development: Journal of Paleontology, v. 83, p. 350–364.CrossRefGoogle Scholar
Guensburg, T.E., Blake, D.B., Sprinkle, J., and Mooi, R., 2016, Crinoid ancestry without Blastozoans: Acta Palaeontologica Polonica, v. 61, p. 253–266.Google Scholar
Guensburg, T.E., Sprinkle, J., Mooi, R., David, B., Lefebvre, B., and Derstler, K., 2020a, Athenacrinus n. gen. and other early echinoderm taxa inform crinoid origin and arm evolution: Journal of Paleontology, v. 94, p. 311–333.CrossRefGoogle Scholar
Guensburg, T.E., Sprinkle, J., Mooi, R., and Lefebvre, B., 2020b, Evolutionary significance of the blastozoan Eumorphocystis and its pseudo-arms. Journal of Paleontology, First View, p. 1–17, https://doi.org/10.1017/jpa.2020.84.Google Scholar
Mooi, R., and David, B.,1997, Skeletal homologies of echinoderms: The Paleontological Society Papers, v. 3, p. 305–335.CrossRefGoogle Scholar
Mooi, R., and David, B., 1998, Evolution within a bizarre phylum: homologies of the first echinoderms: American Zoologist, v. 38: p. 965–974.CrossRefGoogle Scholar
Moore, R.C., 1978, Glossary of crinoid morphological terms, in Moore, R.C., and Teichert, C., eds., Treatise on Invertebrate Paleontology, Part T, Echinodermata 2(2): Geological Society of America, and University of Kansas Press, Boulder, Colorado and Lawrence, Kansas, p. T229–T242.Google Scholar
Moore, R.C., and Laudon, L., 1943a, Trichinocrinus, a new camerate crinoid from Lower Ordovician (Canadian?) rocks of Newfoundland: American Journal of Science, v. 241, p. 262–268.CrossRefGoogle Scholar
Moore, R.C., and Laudon, L.R., 1943b, Evolution and classification of Paleozoic crinoids: Geological Society of America, Special Paper 46, p. 1–153.Google Scholar
Pompeckj, J.A., 1896 (1895), Die fauna des Cambrium von Tejrovic und Skrej in Bohmen: Jahrbuch der k.k. Geologische Reichtanstalt, Wien, v. 45, p. 495–614.Google Scholar
Roemer, C.F., 1855, Erste Periode, Kohlen Gebirge, in Bronn, H.G., ed., Lethaia Geognostica 2 (3rd ed.): Stuttgart, E. Schweitzerbart, p. 1–788.Google Scholar
Ross, D.C., 1966, Stratigraphy of some Paleozoic formations in the Independence quadrangle, Inyo County, California: US Geological Survey Professional Paper 396, p. 1–64.CrossRefGoogle Scholar
Strimple, H.L., and McGinnis, M.R., 1972, A new camerate crinoid from the Al Rose Formation, Lower Ordovician of California: Journal of Paleontology, v. 46, p. 72–74.Google Scholar
Ubaghs, G., 1969, Aethocrinus moorei Ubaghs, n. gen. n. sp., le plus ancien crinoïde dicyclique connu: University of Kansas Paleontological Contributions, Paper 38, p. 1–25.Google Scholar
Ubaghs, G., 1978, Camerata, in Moore, R.C., and Teichert, C., eds., Treatise on Invertebrate Paleontology, Part T, Echinodermata 2(2): Geological Society of America and University of Kansas Press, Boulder, Colorado and Lawrence, Kansas, p. T405–T928.Google Scholar
Wright, D.F., Ausich, W.I., Cole, S.R., Peter, M.E., and Rhenberg, E.C., 2017, Phylogenetic taxonomy and classification of the Crinoidea (Echinodermata): Journal of Paleontology, v. 91, p. 829–846.CrossRefGoogle Scholar