Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-27T06:04:35.418Z Has data issue: false hasContentIssue false

Small problematic phosphatic sclerites from the Ordovician of Iapetus

Published online by Cambridge University Press:  20 May 2016

M. D. Sutton
Affiliation:
Department of Earth Sciences, University of Oxford, Parks Road, Oxford, OX1 3PR, UK,
L. E. Holmer
Affiliation:
Department of Earth Sciences, Norbyv. 22, S-75236 Uppsala, Sweden,
L. Cherns
Affiliation:
Department of Earth Sciences, Cardiff University, PO Box 914, Cardiff CF10 3YE, Wales, UK,

Abstract

Problematic sclerites are common in Cambrian rocks around the world, but much less so in those of the Ordovician. Eurytholia prattensis new genus and species and E. elibata new species, described herein, are rare but widely distributed faunal elements in a narrow stratigraphical interval (Pygodus serra and P. anserinus conodont biozones) within Ordovician beds in an area bordering Iapetus (South Wales, UK; Alabama, USA; Dalarna, Sweden; and North Estonia). Specimens are minute plates (usually less than 1 mm wide), transversely ovoid, and hollow. They are not closely comparable with any previously described fossils. Eurytholia plates are interpreted as dorsal dermal sclerites from an animal of uncertain affinities. The scleritome is provisionally reconstructed as ovoid in form, with sclerites arranged in sub-longitudinal rows.

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

Bengtson, S., Conway Morris, S., Cooper, B., Jell, P. A., and Runnegar., B. S. 1990. Early Cambrian fossils from South Australia. Memoirs of the Association of Australian Palaeontologists, 9, 364 p.Google Scholar
Bengtson, S., and Runnegar., B. S. 1992. Origins of biomineralisation in metaphytes and metazoans, p. 447451. In Schopf, W. S. and Klein, C. (eds.), The Proterozoic Biosphere: A Multidisciplinary Study. Cambridge University Press, Cambridge.Google Scholar
Bischoff, G. C. O. 1981. Cobcrephora n. g., representative of a new Polyplacophoran order phosphatoloricata, with calciumphosphatic shells. Senckenbergiana lethaea, 61:173215.Google Scholar
Brasier, M. D. 1980. Microfossils. George Allen and Unwin London 193 p.Google Scholar
Donoghue, P. C. J. 1998. Growth and patterning in the conodont skeleton. Philosophical Transactions of the Royal Society of London Series B, 353:633666.CrossRefGoogle Scholar
Donovan, S. K., and Paul., C. R. C. 1985. A new possible armoured worm from the Tremadoc of Sheinton, Shropshire. Proceedings of the Geologists Association, 96:8791.CrossRefGoogle Scholar
Fortey, R. A., Harper, D. A. T., Ingham, J. K., Owen, A. W., and Rushton., A. W. A. 1995. A revision of Ordovician series and stages from the historical type area. Geological Magazine, 132:1530.CrossRefGoogle Scholar
Grahn, Y., and Bergström., S. M. 1984. Lower Middle Ordovician chitinozoa from the southern Appalachians, United States. Review of Palaeobotany and Palynology, 43:89122.CrossRefGoogle Scholar
Hinz, I. C. U, Kraft, P., Mergl, M., and Müller, K. J., J., K. 1990. The problematic Hadimopanella, Kaimenella, Milaculum and Utahphospha identified as sclerites of Palaeoscolecida. Lethaia, 23:217221.CrossRefGoogle Scholar
Högström, A. 1997. Machaeridians from the upper Wenlock (Silurian) of Gotland. Palaeontology, 40:817831.Google Scholar
Holmer, L. E. 1989. Middle Ordovician phosphatic inarticulate brachiopods from Västergötland and Dalarna, Sweden. Fossils and Strata, 26, 172 p.Google Scholar
Kaljo, D., and Nestor., H. 1990. Field Meeting Estonia 1990—An excursion guidebook. Institute of Geology. Estonian Academy of Sciences, Tallinn, 209 p.Google Scholar
Müller, K. J. 1973. Milaculum n. g., ein phosphatisches Mikrofossil aus dem Altpalaeozoikum. Palaeontologische Zeitschrift, 47:217228.CrossRefGoogle Scholar
Ramsköld, L., and Hou., X. 1991. New Early Cambrian animal and onychophoran affinities of enigmatic metazoans. Nature (London), 351:225228.CrossRefGoogle Scholar
Rhoads, D. C. 1962. Microfossils of problematic affinity from the Maquoketa Formation of eastern Iowa and western Illinois. Journal of Paleontology, 36:13341340.Google Scholar
Runnegar, B., and Bengtson., S. 1990. Origin of Hard Parts—Early Skeletal Fossils, p. 2429. In Briggs, D. E. G. and Crowther, P. R. (eds.), Paleobiology—a Synthesis. Blackwell, Oxford.Google Scholar
Sanders, R. B. 1966. The incertae sedis group tegmates revealed as plates of a chiton. Jouranl of Paleontology, 40:12401241.Google Scholar
Sutton, M. D., Bassett, M. G., and Cherns., L. C. 1999. Lingulate brachiopods from the lower Ordovician of the Anglo-Welsh Basin, Part 1. Monograph of the Palaeontographical Society, London, 179 p., 6 pls.Google Scholar
Torsvik, T. H. 1998. Palaeozoic palaeogeography: a North Atlantic viewpoint. GFF, 120:109118.CrossRefGoogle Scholar
Williams, A. 1953. The geology of the Llandeilo District, Carmarthenshire. Quarterly Journal of the Geological Society, London, 108:177208.CrossRefGoogle Scholar