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Calymene quadrata King, 1923 and allied species of trilobites from the Ashgill Series of North Wales

Published online by Cambridge University Press:  01 May 2009

David Price
Affiliation:
Sedgwick Museum, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ

Summary

Calymene quadrata King is re-described. Two new species of similar age and provenance are erected and considered to be closely allied to quadrata; all three forms are thought to be best placed in genus Gravicalymene Shirley. G. pontilis sp.nov., the stratigraphically oldest form suggests derivation of the group from an ancestor such as G. deani Ingham. G. arcuata sp.nov. is the youngest form. Variation in the preglabellar area between the three forms argues for an expansion of the diagnosis of genus Gravicalymene; this would allow it to contain forms previously placed in genus Sthenarocalymene Siveter.

Type
Articles
Copyright
Copyright © Cambridge University Press 1982

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References

Dean, W. T. 1962. The trilobites of the Caradoc Series in the Cross Fell Inlier of northern England. Bull. Br. Mus. nat. Hist. (Geol.), 7, 65134, pls 6–18, 5 text-figs.Google Scholar
Ingham, J. K. 1977. A monograph of the upper Ordovician trilobites from the Cautley and Dent districts of Westmorland and Yorkshire. Palaeontogr. Soc. (Monogr.) 3, 89121, pls 19–127.Google Scholar
King, W. B. R. 1923. The Upper Ordovician rocks of the south-western Berwyn Hills. Q. Jl geol. Soc. Lond. 79, 487507, pl. 26.CrossRefGoogle Scholar
King, W. B. R. 1928. The geology of the district around Meifod (Montgomeryshire). Q. Jl geol. Soc. Lond. 84, 671702.CrossRefGoogle Scholar
McNamara, K. J. 1979. Trilobites from the Coniston Limestone Group (Ashgill Series) of the Lake District, England. Palaeontology 22, 5392, pls 7–12.Google Scholar
Milne-Edwards, H. 1840. Histoire naturelle des Crustacés, comprenant l'Anatomie, la physiologie et la classification de ces animaux. Vol. 3, 1638. Paris.Google Scholar
Moore, R. C. (ed.) 1959. Treatise on Invertebrate Palaeontology. Part O. Arthropoda 1. Geol. Soc. Am. and Univ. Kansas Press.Google Scholar
Price, D. 1974. Trilobites from the Sholeshook Limestone (Ashgill) of South Wales. Palaeontology 17, 841–68, pls 112–16.Google Scholar
Reed, F. R. C. 1935. The Lower Palaeozoic trilobites of Girvan. Supplement No. 3. Palaeontogr. Soc. (Monogr.), 64 pp., 4 pls.Google Scholar
Shirley, J. 1936. Some British trilobites of the family Calymenidae. Q. Jl geol. Soc. Lond. 92, 384422, pls 29–31.CrossRefGoogle Scholar
Siveter, D. J. 1977. The Middle Ordovician of the Oslo Region, Norway. 27. Trilobites of the family Calymenidae. Norsk. Geol. Tidsskr. 56, 335–96, 11 pls.Google Scholar
Siveter, D. J. 1979. Metacalymene Kegel, 1927, a calymenid trilobite from the Kopanina Formation (Silurian) of Bohemia. J. Paleont. 53, 367–79, pls 1–3.Google Scholar
Siveter, D. J. 1980. Evolution of the Silurian trilobite Tapinocalymene from the Wenlock of the Welsh borderlands. Palaeontology 23, 783802, pls 97–101.Google Scholar
Temple, J. T. 1975. Early Llandovery trilobites from Wales with notes on British Llandovery calymenids. Palaeontology 18, 137–59, pls 25–7.Google Scholar
Whittington, H. B. 1938. The geology of the district around Llansantffraid-ym-Mechain, Montgomeryshire. Q. Jl geol. Soc. Lond. 94, 423–57, pls 38, 39.CrossRefGoogle Scholar
Whittington, H. B. 1971. Silurian calymenid trilobites from the United States, Norway and Sweden. Palaeontology 14, 455–77, pls 83–9.Google Scholar