Radiate shell structures in Paleozoic Myodocopid and Palaeocopid ostracodes are epigenetic

I. G. Sohn

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Radiate shell structures in Paleozoic Myodocopid and Palaeocopid ostracodes are epigenetic

I. G. Sohn

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Abstract

The radiate structures in the shell of Paleozoic ostracodes are interpreted to be epigenetic in origin. On the basis of this interpretation, the genus Radiicypridina Bless, 1973, is a junior synonym of Eocypridina Kesling and Ploch, 1960. The type-series of Eocypridina radiata (Jones, Kirkby, and Brady, 1874), from the Coal Measures of Scotland, is illustrated, and a lectotype is designated. Eocypridina aciculata , (Scott and Summerson, 1943) is a valid species, but the more elongated specimens they identified as Cypridina radiata Jones, Kirkby, and Brady, 1874, from the same collection, belong in E. aciculata . The variation in lateral outline of specimens in the Hance Formation of Kentucky is due to the orientation of the valves in the rock.

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I. G. Sohn. 1977. Radiate shell structures in Paleozoic Myodocopid and Palaeocopid ostracodes are epigenetic. https://pubs.usgs.gov/publication/70232980

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