Caron (1985):
R. hexacamerata differs from other Rugoglobigerina species in generally having 6 globular chambers froming the last whorl, increasing only slowly in size. The species evolved from R. rugosa which differs in having only 4-5 chambers, increasing more rapidly in size.
Van Eijden & Smit (1991):
Remarks. R. hexacamerata occurs in the Maestrichtian and is usually rare. Intermediate forms with its ancestor, Archaeoglobigerina cretacea (d'Orbigny, 1840), and its descendant, Rugotruncana subcircumnodifer (Gandolfi, 1955), occur. |
Brönnimann,P. (1952): Globigerinidae from the upper Cretaceous (Cenomanian-Maestrichtian) of Trinidad, B.W.I. . Bulletins of American paleontology Vol. 34 p. 5-71
Gandolfi,R. (1955): The genus Globotruncana in Northeastern Colombia . Bulletins of American paleontology Vol. 36 p. 7-118
Caron,M. (1985): Cretaceous planktic foraminifera. In: Plankton stratigraphy Eds: Bolli, H.M.Saunders, J.B.Perch-Nielsen, K. p. 17–86
Van Eijden,A.J.M. and Smit,J. (1991): Eastern Indian Ocean Cretaceous and Paleogene quantitative biostratigraphy. In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 121 Eds: Weissel, J.Peirce, J.Taylor, E.Alt, J. p. 77-123
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