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Indications of polypides in feeding zooids and polymorphs in Lower Paleozoic trepostomata (Bryozoa)

Published online by Cambridge University Press:  14 July 2015

Richard S. Boardman
Richard S. Boardman*
Affiliation:
Curator Emeritus, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560
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Abstract

Delicate symmetrical structures in living chambers of autozooecia of some lower Paleozoic species of the order Trepostomata have been interpreted as indications of polypides with little further elaboration. Applications of the anatomy, mode of skeletal growth, and functional requirements basic to living species permit recognition of a few organs of these partially preserved polypides, their functions, and their relationships to enclosing skeletons. Only one basic polypide anatomy is indicated in lower Paleozoic trepostome species, in contrast to the wide diversity of polypide anatomy and their lack of correlation with skeletal characteristics in living stenolaemates. In general, the longer the evolutionary history, the greater the diversity of skeletal morphology in stenolaemates. Apparently, polypide diversity and lack of correlation with skeletal morphology also have increased over time.

The complex skeletal septa in autozooecial apertures of the lower Paleozoic trepostome Hallopora have been interpreted as reflecting an organ of full-sized feeding polypides. Applications of the basic biological concepts of living species suggest that the septa provided reduced skeletal apertures to fit smaller polypides of polymorphs that secondarily occupied the living chambers of full-sized degenerated feeding polypides.

Type
Research Article
Information
Journal of Paleontology , Volume 73 , Issue 5 , September 1999 , pp. 803 - 815
Copyright
Copyright © The Paleontological Society 

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References

Bancroft, A. J. 1986. Secondary nanozooecia in some upper Paleozoic fenestrate Bryozoa. Palaeontology, 29:207–212.Google Scholar
Bassler, R. S. 1903. The structural features of the bryozoan genus Homotrypa, with descriptions of species from the Cincinnatian Group. Proceedings of the United States National Museum, 26:565–591.CrossRefGoogle Scholar
Bassler, R. S. 1911. The early Paleozoic Bryozoa of the Baltic Provinces. U.S. National Museum Bulletin, 77:1–382.Google Scholar
Boardman, R. S. 1960. Trepostomatous bryozoa of the Hamilton Group of New York State. U.S. Geological Survey Professional Paper, 340, 87 p.Google Scholar
Boardman, R. S. 1971. Mode of growth and functional morphology of autozooids in some Recent and Paleozoic tubular Bryozoa. Smithsonian Contributions to Paleobiology, 8, 51 p.Google Scholar
Boardman, R. S. 1983. General features of the class Stenolaemata, p. G50–G137. In Robison, R. A. (ed.), Treatise on Invertebrate Paleontology, Pt. G, Bryozoa, Revised. Geological Society of America and University of Kansas Press, Lawrence, 625 p.Google Scholar
Boardman, R. S. 1998. Reflections on the morphology, anatomy, evolution, and classification of the class Stenolaemata (Bryozoa). Smithsonian Contributions to Paleobiology, 86, 60 p.Google Scholar
Boardman, R. S., and McKinney, F. K. 1976. Skeletal architecture and preserved organs of four-sided zooids in convergent genera of Paleozoic Trepostomata (Bryozoa). Journal of Paleontology, 50:25–78.Google Scholar
Boardman, R. S., McKinney, F. K., and Taylor, P. D. 1992. Morphology, anatomy, and systematics of the Cinctiporidae, new family (Bryozoa, Stenolaemata). Smithsonian Contributions to Paleobiology, 70, 81 p.Google Scholar
Borg, F. 1926. Studies on Recent cyclostomatous Bryozoa. Zoologiska Bidrag Fran Uppsala, 10:181–507.Google Scholar
Conti, S., and Serpagli, E. 1984. A new interpretation of the anthozoan Septodaeum Bischoff, 1978 as a bryozoan. Bollettino della Societa Paleontologica Italiana, 23:3–20.Google Scholar
Conti, S., and Serpagli, E. 1987. Functional morphology of the cap-like apparatus in autozooids of a Paleozoic trepostome bryozoan. Lethaia, 20:1–20.CrossRefGoogle Scholar
Corneliussen, E. F., and Perry, T. G. 1973. Monotrypa, Hallopora, Amplexopora, and Hennigopora (Ectoprocta) from the Brownsport Formation (Niagaran), western Tennessee. Journal of Paleontology, 47:151–220.Google Scholar
Cumings, E. R., and Galloway, J. J. 1915. Studies of the morphology and histology of the Trepostomata or monticuliporoids. Geological Society of America, 26:349–374.CrossRefGoogle Scholar
d'Orbigny, A. D. 1849. Description de quelques genres nonveaux de Mollusques Bryozoaires. Revue et Magasin de Zoologie [2], I:499–504.Google Scholar
Duncan, H. 1939. Trepostomatous Bryozoa from the Traverse Group of Michigan. Contributions from the Museum of Paleontology, University of Michigan, V, no. 10:171–270.Google Scholar
Hall, J. 1852. Organic remains of the lower middle division of the New York system. Natural History of New York, Pt. 6, Paleontology of New York, 2, 362 p.Google Scholar
Johnston, G. 1838. A history of the British Zoophytes. W. H. Lizars, Edinburgh, Scotland, 341 p.Google Scholar
MacGillvray, P. H. 1881. On two new genera of Polyzoa. Transactions and Proceedings of the Royal Society of Victoria, 17:15–19.Google Scholar
McKinney, F. K. 1977. Functional interpretation of lyre-shaped Bryozoa. Paleobiology, 3:90–97.CrossRefGoogle Scholar
McKinney, F. K. 1994. The bryozoan genera Lyropora and Lyroporidra (order Fenestrida, family Polyporidae) in Upper Mississippian (Chester) rocks of eastern North America. American Museum Novitates, no. 3111, 31 p.Google Scholar
Morrison, S. J., and Anstey, R. L. 1979. Ultrastructure and composition of brown bodies in some Ordovician trepostome bryozoans. Journal of Paleontology, 53:943–949.Google Scholar
Nicholson, H. A. 1879. On the structure and affinities of the “tabulate corals” of the Paleozoic Period, with critical descriptions of illustrative species. William Blackwood & Sons, Edinburg, Scotland, 342 p.Google Scholar
Nicholson, H. A. 1881. On the structure and affinities of the genus Monticulipora and its subgenera, with critical descriptions of illustrative species. William Blackwood & Sons, Edinburgh, Scotland, 240 p.Google Scholar
Nicholson, H. A., and Etheridge, R. 1877. On Prasopora Grayae, a new genus and species of Silurian corals. Annals and Magazine of Natural History, fourth series, 20:388–392.CrossRefGoogle Scholar
Nielsen, C., and Pedersen, K. J. 1979. Cystid structure and protrusion of the polypide in Crisia (Bryozoa, Cyclostomata). Acta Zoologica (Stockholm), 60:65–88.CrossRefGoogle Scholar
Owen, D. E. 1969. Wenlockian Bryozoa from Dudley, Niagara and Gotland and their palaeogeographic implications. Palaeontology, 12:621–636.Google Scholar
Rominger, C. 1866. Observations on Chaetetes and some related genera, in regard to their systematic position; with an appended description of some new species. Proceedings of the Academy of Natural Sciences of Philadelphia, 18:113–123.Google Scholar
Ross, J. P. 1967. Champlainian Ectoprocta (Bryozoa), New York State. Journal of Paleontology, 41:632–648.Google Scholar
Silen, L., and Harmelin, J.-G. 1974. Observations on living Diastropidae (Bryozoa, Cyclostomata) with special regard to polymorphism. Acta Zoologica (Stockholm), 55:81–96.CrossRefGoogle Scholar
Ulrich, E. O. 1879. Descriptions of new genera and species of fossils from the Lower Silurian about Cincinnati. Journal of Cincinnati Society of Natural History, 2:8–30.Google Scholar
Ulrich, E. O. 1882. American Paleozoic Bryozoa. Journal of Cincinnati Society of Natural History, 5:121–175; 232-257.Google Scholar
Ulrich, E. O. 1883. American Paleozoic Bryozoa. Journal of Cincinnati Society of Natural History, 6:245–279.Google Scholar
Ulrich, E. O. 1886. Report on the Lower Silurian Bryozoa with preliminary descriptions of some new species. Minnesota Geology Natural History Survey Annual Report, 14:57–103.Google Scholar
Ulrich, E. O. 1890. Paleozoic Bryozoa. Illinois Geological Survey, 8:283–688.Google Scholar
Ulrich, E. O. 1893 (1895). On Lower Silurian Bryozoa of Minnesota. Geological and Natural History Survey of Minnesota, Final Report, 3, pt. 1:99–332.Google Scholar
Ulrich, E. O., and Bassler, R. 1904. A Revision of the Paleozoic Bryozoa. Smithsonian Miscellaneous Collections, 47:15–55.Google Scholar
Utgaard, J. 1973. Mode of colony growth, autozooids, and polymorphism in the bryozoan order Cystoporata, p. 317–360. In Boardman, R. S., Cheetham, A. H., and Oliver, W. A. Jr. (eds.), Animal Colonies. Dowden, Hutchinson, and Ross; Stroudsburg, Pennsylvania.Google Scholar
Vinassa de Regny, P. E. 1921. Sulla classificazione dei Treptostomidi. Atti della Societa Italiana di Scienze Naturali, 59:212–231.Google Scholar
Waters, A. W. 1879. On the Bryozoa of the Bay of Naples. Annals and Magazine of Natural History, fifth series, 3:267–281.CrossRefGoogle Scholar