Camptonectes milleri (J. de C. Sowerby in Fitton, 1836)
SOWERBY, J. DE C. 1836. Appendix A. Descriptive Notes respecting the Shells figured in Plates XI to XXIII. In W. H. Fitton (1836): Observations on some of the Strata between the Chalk and the Oxford Oolite in the South-east of England, 335-349. Transactions of the Geological Society of London [2nd Series], 4 (2): 103-388. [p. 342, pl. 17, figs. 19a, 19b]
1836 Pecten milleri J. de C. Sowerby in Fitton, 1836
«Variability:
In some specimens ribs are present : they are elevated above the disc surface (WOODS, 1902, pI. 31, fig. 4 a & 6 b). On other specimens the shell is smooth (i.e. the disc-surface is divided into thin radial ribbons by the Camptonectes striae). The rather unusual ornamentation makes it difficult to decide the exact generic position of Pecten milleri: it is the only Cretaceous species that combines «Chlamys» and Camptonectes characteristics. For analogous Jurassic species ARKELL proposed the new genus Camptochlamys (ARKELL, 1930). Pecten milleri, however, is not a Camptochlamys because it lacks the typical concentric ornamentation. Apart from the ribs on some specimens it has all the Camptonectes characteristics and, for instance, is much more convex than Camptochlamys. Differentiation
Left valves of Pecten milleri are very similar to Camptonectes virgatus (NILSSON), particularly when they do not have ribs. The only real difference is that the Camptonectes-sculpture is less pronounced in P. milleri, on right and left valves, and the «diverging» lines are almost straight and rarely divide. The other Camptonectes-species differ by their size and/or have a well developed macrosculpture. Generic attribution
Whether Pecten milleri SOWERBY really belongs to Camptonectes, I have not been able to ascertain (see under Variability). At present it seems safer to use Camptonectes? milleri (SOWERBY).» DHONDT, A. V. 1972. Systematic revision of the Chlamydinae (Pectinidae, Bivalvia, Mollusca) of the European Cretaceous. Part 1: Camponectes. Bulletin de l’Institut Royal des Sciences Naturelles de Belgique, 48 (3): 1-60, pls. 1, 2. [p. 43, 44]
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P. (Chlamys) Milleri, Sow.; H. Woods, 1899-1902, A monograph of the Cretaceus Lamellibranchia of England, plate 31, figures 3-6.
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