Hostname: page-component-76fb5796d-qxdb6 Total loading time: 0 Render date: 2024-04-28T06:13:09.964Z Has data issue: false hasContentIssue false

Paleoecology of hardground encrusting and commensal crinoids, Middle Ordovician, Tennessee

Published online by Cambridge University Press:  20 May 2016

Thomas E. Guensburg*
Affiliation:
Physical Science Division, Rock Valley College, Rockford, Illinois 61111

Abstract

Aspects of functional morphology are examined and lifestyles proposed for seven exceptionally well-preserved crinoids from the Middle Ordovician Lebanon Limestone, Middle Tennessee. Potential ranges of motion are based on plate shapes, articular surfaces of attachment, and feeding structures. This diverse group of crinoids includes disparid inadunates (Columbicrinus crassus and Tryssocrinus endotomitus), a hybocrinid (Hybocrinus bilateralis), reteocrinids (Reteocrinus polki and R. variabilicaulis), and rhodocrinitid camerates (Archaeocrinus snyderi and Gustabilicrinus plektanikaulos). Using attachment structures as the basis, these crinoids can be divided into two groups: encrusters and commensals. Encrusters are the most diverse and include all taxa except the rhodocrinitids. They have a small discoidal holdfast and xenomorphic column. Proxistele-mesisteles were holomeric or pentameric. Flexure potential of this region of the column in disparids was increased by wider ligament gaps at nodal-internodal articulations; in other taxa flexure was enhanced by increasing the frequency of columnals. Short dististeles are polymeric or a plate mosaic. This region functioned as a resilient buffer between the mesistele and holdfast. Columns as a whole had moderate flexure potential. Feeding-structure design was varied, although all but Hybocrinus bilateralis had pinnulate or nonpinnulate parabolic filtration fans. Hybocrinus bilateralis had atomous arms arrayed in a bilaterally symmetrical pattern; the symmetry plane was oriented parallel to prevailing currents. Commensals in the Lebanon are the rhodocrinitids. Their attachment structures are characterized by a long distally tapering column terminating in a coil. Densely pinnulate arms formed a well-developed parabolic filtration fan.

Encrusters were limited to hardgrounds or skeletal substrata. Commensals were more opportunistic, utilizing a variety of substrates, and they were widespread in Lebanon subenvironments including those with both soft and hard seafloors. Lebanon hardground assemblages are characterized by high diversity, particularly among crinoids and bryozoans. They are strikingly tiered according to elevation above the seafloor (and probably additionally by feeding limitations). This assemblage was the result of longterm coevolution in association with hardgrounds.

Ontogenetic development of the column of encrusting crinoids indicates that the evolution of holomeric columnals occurred through a simpler sequence than previously proposed and need not have included gradual alignment of offset pentameres as intermediate steps. Columnals evolved from a poorly organized plate mosaic through a polymeric stage.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ausich, W. I. 1980. A model for niche differentiation in Lower Mississippian crinoid communities. Journal of Paleontology, 54:273288.Google Scholar
Ausich, W. I. 1983. Functional morphology and feeding dynamics of the Early Mississippian crinoid Barycrinus asteriscus. Journal of Paleontology, 57:3141.Google Scholar
Ausich, W. I., and Bottjer, D. J. 1982. Tiering in suspension-feeding communities on soft substrata throughout the Phanerozoic. Science, 216:173174.Google Scholar
Bennedict, G. L. 1974. Lithofacies and depositional environments of the Lebanon Limestone (Ordovician) in central and east-central Tennessee. Unpubl. , Vanderbilt University, Nashville, Tennessee, 168 p.Google Scholar
Breimer, A. 1978. General morphology (of) recent crinoids, p. T9T58. In Moore, R. C. and Teichert, C. (eds.), Treatise on Invertebrate Paleontology, Pt. T, Echinodermata 2. The Geological Society of America and the University of Kansas Press, Lawrence.Google Scholar
Brett, C. E. 1981. Terminology and functional morphology of attachment structures in pelmatozoan echinoderms. Lethaia, 14:343370.Google Scholar
Brett, C. E. 1984. Autecology of Silurian pelmatozoan echinoderms. Special Papers in Palaeontology, 32:87120.Google Scholar
Brett, C. E., and Brookfield, M. E. 1984. Morphology, faunas and genesis of Ordovician hardgrounds from southern Ontario, Canada. Palaeogeography, Palaeoclimatology, Palaeoecology, 46:233290.Google Scholar
Brett, C. E., and Liddell, W. D. 1978. Preservation and paleoecology of a Middle Ordovician hardground community. Paleobiology, 4:329348.CrossRefGoogle Scholar
Brower, J. C., and Veinus, J. 1974. Middle Ordovician crinoids from southwestern Virginia and eastern Tennessee. Bulletins of American Paleontology, 66:1125.Google Scholar
Donovan, S. K. 1988. Functional morphology of synarthrial articulations in the crinoid stem. Lethaia, 21:169175.Google Scholar
Donovan, S. K. 1990. Functional morphology of synostosial articulations in the crinoid column. Lethaia, 23:291296.Google Scholar
Donovan, S. K., and Franzen-Bengston, C. 1988. Myelodactylid crinoid columnals from the Lower Visby Beds (Llandoverian) of Gotland. Geologiska Foreningens i Stockholm Forhandlingar, 110:6979.Google Scholar
Eckert, J. D. 1984. Early Llandovery crinoids and stellaroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada. Royal Ontario Museum Life Sciences Contributions, 137, 83 p.Google Scholar
Grimmer, J. C., Holland, N. D., and Messing, C. G. 1984. Fine structure of the stalk of the bourgueticrinid sea lily Democrinus conifer (Echinodermata: Crinoidea). Marine Biology, 81:163176.Google Scholar
Grimmer, J. C., Holland, N. D., and Hayami, I. 1985. Fine structure of the stalk of an isocrinid sea lily (Metacrinus rotundus) (Echinodermata, Crinoidea). Zoomorphology, 105:3950.Google Scholar
Guensburg, T. E. 1984. Echinodermata of the Middle Ordovician Lebanon Limestone, central Tennessee. Bulletins of American Paleontology, 86:1100.Google Scholar
Guensburg, T. E. 1988. Functional interpretation and phylogenetic significance of the column in attached and associated commensal Blackriveran (mid-Ordovician) crinoids, p. 798. In Burke, R. D., Mladenov, P. V., Lambert, P., and Parsley, R. L. (eds.), Echinoderm Biology, Proceedings of the Sixth International Echinoderm Conference. A. A. Balkema, Rotterdam, Brookfield.Google Scholar
Kammer, T. W., and Ausich, W. I. 1987. Aerosol suspension feeding and current velocities: distributional controls for late Osagean crinoids. Paleobiology, 13:379395.CrossRefGoogle Scholar
Kelly, S. M. 1986. Classification and evolution of the class Crinoidea. Fourth North American Paleontological Convention, Abstract:A23.Google Scholar
Kolata, D. R. 1975. Middle Ordovician echinoderms from northern Illinois and southern Wisconsin. The Paleontological Society, Memoir 7, 74 p.Google Scholar
Kolata, D. R. 1982. Camerate crinoids, p. 170205. In Sprinkle, J. (ed.), Echinoderm faunas from the Bromide Formation (Middle Ordovician) of Oklahoma. The University of Kansas Paleontological Contributions, Monograph 1, University of Kansas Press, Lawrence.Google Scholar
Lane, N. G., and Macurda, D. B. 1975. New evidence for muscular articulations in Paleozoic crinoids. Paleobiology, 1:5962.Google Scholar
Lewis, R. D. 1982. Holdfasts, p. 5767. In Sprinkle, J. (ed.), Echinoderm faunas from the Bromide Formation (Middle Ordovician) of Oklahoma. The University of Kansas Paleontological Contributions, Monograph 1, University of Kansas Press, Lawrence.Google Scholar
Lewis, R. D., and Roux, M. 1981. The skeletal morphology of the isocrinid crinoids Annacrinus wyvillethompsoni and Diplocrinus maclearanus. The University of Michigan Museum of Paleontology, Contributions, 25:169219.Google Scholar
McIntosh, G. 1982. Feeding strategies in lower Paleozoic cladid inadunate crinoids. Geological Society of America, Abstracts with Programs, 14:40.Google Scholar
Meyer, D. L. 1971. The collagenous nature of problematical ligaments in crinoids (Echinodermata). Marine Biology, 9:235241.Google Scholar
Riddle, S. W., Wulff, J. I., and Ausich, W. I. 1988. Biomechanics and stereomic microstructure of the Gilbertsocrinus tuberosus column, p. 641648. In Burke, R. D., Mladenov, P. V., Lambert, P., and Parsley, R. L. (eds.), Echinoderm Biology, Proceedings of the Sixth International Echinoderm Conference (1987). A. A. Balkema, Rotterdam, Brookfield.Google Scholar
Sardeson, F. W. 1908. Discoid crinoid roots and Camerocrinus. Journal of Geology, 49:3546.Google Scholar
Seilacher, A., Drozdzewski, G., and Haude, R. 1968. Form and function of a pseudoplanktonic crinoid (Seirocrinus). Palaeontology, 11:275282.Google Scholar
Sevastopulo, G. D., and Lane, N. G. 1988. Ontogeny and phylogeny of disparid crinoids, p. 245254. In Paul, C. R. C. and Smith, A. B. (eds.), Echinoderm Phylogeny and Evolutionary Biology. Liverpool Geological Society, Clarendon Press, Oxford.Google Scholar
Siewers, F. deS. 1988. Hardgrounds in the Middle Ordovician Lebanon Limestone, Central Basin, Tennessee. Unpubl. , Vanderbilt University, Nashville, Tennessee, 83 p.Google Scholar
Springer, F. 1911. On a Trenton echinoderm fauna at Kirkfield, Ontario. Canada Department of Mines, Geological Survey Branch, Memoir 15, 47 p.CrossRefGoogle Scholar
Sprinkle, J. 1973. Morphology and evolution of blastozoan echinoderms. Harvard University, Museum of Comparative Zoology, Special Publication, 283 p.Google Scholar
Sprinkle, J. (ed.). 1982. Echinoderm faunas from the Bromide Formation (Middle Ordovician) of Oklahoma. The University of Kansas Paleontological Institute, Monograph 1, 369 p.Google Scholar
Sprinkle, J., and Moore, R. C. 1978. Hybocrinida, p. T564T574. In Moore, R. C. and Teichert, K. (eds.). Treatise on Invertebrate Paleontology, Pt. T, Echinodermata 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Strimple, H. L. 1975. Bottom dwelling hybocrinids from Kentucky. Southeastern Geology, 17:5153.Google Scholar
Stukalina, G. A. 1967. On taxonomic features of articulated stems of crinoids. Vses. Nauchno-Issled. Geological Institute, Trudy, new series, 129:200206.Google Scholar
Ubaghs, G. 1978a. Skeletal morphology of fossil crinoids, p. T58T216. In Moore, R. C. and Teichert, K. (eds.), Treatise on Invertebrate Paleontology, Pt. T, Echinodermata 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Ubaghs, G. 1978b. Camerata, p.T408T519. In Moore, R. C. and Teichert, K. (eds.), Treatise on Invertebrate Paleontology, Pt. T, Echinodermata 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Ulrich, E. O. 1925. New classification of the “Heterocrinidae,” p. 82104. In Foerste, A. F., Upper Ordovician Faunas of Ontario and Quebec. Geological Survey of Canada, Memoir 138.Google Scholar
Warn, J., and Strimple, H. L. 1977. The disparid inadunate superfamilies Homocrinacea and Cincinnaticrinacea (Echinodermata: Crinoidea), Ordovician-Silurian, North America. Bulletins of American Paleontology, 72:1138.Google Scholar
Wanless, H. R., Tedesco, L. P., and Tyrrell, K. M. 1988. Production of subtidal tubular and surficial tempestites by Hurricane Kate, Caicos Platform, British West Indies. Journal of Sedimentary Petrology, 58:739750.Google Scholar
Wilson, M. A., and Palmer, T. J. 1990. A review of evolutionary trends in carbonate hardground communities. The Paleontological Society Special Publications, 5:137152.Google Scholar