Cover plate

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Fig. 1. Cover plate and foramenal plate in Challengerella bradyi Billman et alii from the Gulf of Aqaba. Recent. SEM graphs. A-B: dissected specimens in oblique ventral view. C: young specimen, ventral view. Note incipient umbilical pile against which the foliar walls are beginning to fuse, covering the spiral interlocular space. D: dorsal (spiral) view of adult megalospheric specimen. E: Detail showing foraminal and cover-plates. Colours corresponding to those used in the models. White arrow: loop-hole. F: general model showing position of plates and communications. Note position of loop-hole (red arrow). G: Detail of umbilical structures in last three chambers. Note the separation of streaming chamber plasm through successive foramina (blue arrow) and circulation in the umbilical interlocular space (black arrow) by the umbilical structures. Models schematic, not to scale, after Hottinger, 2000. a: aperture; cp: cover plate; csut: chamber (septal) suture; f: foramen; fo: folium; foa: foliar aperture; fp: foramenal plate; isp: interlocular (intrasepal) space; lh: loop-hole; n: notch; pil: umbilical plug; s: septum; sf: septal flap; suc: spiral umbilical interlocular space, transformed into spiral canal when covered by foliar extensions; u: umbilicus; ulch: ultimate chamber; vc: funnel (vertical canal); wsut: whorl (spiral) suture; (Hottinger, 2006; fig. 34 [1] CC/BY-NC-SA)


  • according to Hottinger (2006):

COVER PLATE - (= umbilical cover plate); (retroparies, pars auct.); a more or less folded, imperforate extension of the septal flap into the preceding chamber through the intercameral foramen, separating - in the preceding chamber - the main chamber lumen from a foliar chamberlet. Usually attached to a preceding foramenal plate. It is a secondary feature, never present in the ultimate chamber and thus not homologous with a primary foramenal plate or umbilical plate. Compare also: sealing plate.

See also


Hottinger (2000), Functional morphology of benthic foraminiferal shells, envelopes of cells beyond measure. In: Lee J.J. & Hallock P. (eds.), Advances in biology of Foraminifera, Micropaleontology, New York, vol. 46, suppl. 1, p. 57-86.

Hottinger (2006), Illustrated glossary of terms used in foraminiferal research. Carnets de Géologie, Memoir 2, ISSN 1634-0744

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