Ellipsoscapha Stephenson 1941
Ellipsoscapha ? sp. Figs 36 D–F Material. MGUH 33325 and an external and internal mould in sample SR.736.A collected in connection with this study. Occurrence. Lithified top of the Maastrichtian Højerup Member at Rødvig and Knøsen, Stevns Klint. Description. Shell involute, elongated cylindrical wit...
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Format: | Other/Unknown Material |
Language: | unknown |
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Zenodo
2019
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Online Access: | https://doi.org/10.5281/zenodo.5583013 http://treatment.plazi.org/id/BF18F633A9A8FF4D2B9CC2B7FB99F923 |
Summary: | Ellipsoscapha ? sp. Figs 36 D–F Material. MGUH 33325 and an external and internal mould in sample SR.736.A collected in connection with this study. Occurrence. Lithified top of the Maastrichtian Højerup Member at Rødvig and Knøsen, Stevns Klint. Description. Shell involute, elongated cylindrical with a thick wall. Spire pit closed, only seen as a slight apical impression. Aperture long and narrow with weakly curved outer and inner lip; inner lip covered by well developed callus reaching down onto short columella. Columella smooth; columellar fold lacking or strongly effaced. Surface with spiral grooves on base. Measurements. MGUH 33325 is 6.55 mm high and 3.5 mm wide. Remarks. This taxon differs from typical species of the genus by lacking spiral grooves on the central part of the shell; by the unpitted grooves and by the rather broad callus on the parietal region. This would suggest that it should not be regarded as a true Ellipsoscapha , but as the material is limited and the taxon furthermore shows a strong resemblance to Ellipsoscapha sp. of Kollmann & Peel (1983) from the Palaeocene of Greenland, it is placed in this genus for the time being. Ellipsoscapha ? sp. is distinguished from the Palaeocene Ellipsoscapha sp. of Kollmann & Peel (1983) from Greenland by the restricted spiral sculpture and possible by the presence of a shallow spire pit. It is distinguished from the above described cylichniid taxa from Denmark by the narrow cylindrical shell lacking a columellar fold and spire pit, and by the spiral grooves restricted to the base. Published as part of Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, pp. 1-196 in Zootaxa 4654 (1) on page 169, DOI:10.11646/zootaxa.4654.1.1, http://zenodo.org/record/3365803 |
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