Kennett & Srinivasan (1983):
Test very low trochospiral, spiral side almost flat; equatorial periphery lobulate, axial periphery broadly rounded; chambers spherical, five in the final whorl, increasing rapidly in size as added; sutures on both spiral and umbilical sides slightly curved to nearly radial, depressed; surface distinctly cancellate, with large pores set in deep hexagonal-funnel-like pore pits ; umbilicus fairly wide, partly covered by apertural plate; aperture interiomarginal, umbilical-extraumbilical, a very low arch bordered by a distinct apertural plate or thick rim. |
Kennett & Srinivasan (1983):
Gd. hexagona exhibits a wide range of variation in the inflation and size of chambers and in apertural characters. It is usually distinguished by its five to six globular, inflated chambers in the final whorl, which are individually more distinct and less embracing than in Gd. variabilis.
Srinivasan (1975):
Globorotaloides suteri (Bolli) is probably synonymous
with this species, as has been mentioned by
Todd (1964) and Lipps (1964). The relative abundance
of this species may be due to its solution-resistant test.
A very close similarity in surface ultramicrostructure of
G. hexagona and of Protentella (Clavatorella) bermudezi
suggests a close phylogenetic relationship between the
two taxa.
Chaisson & Leckie (1993):
Remarks: This is a relatively rare species in Hole 806B. The spiral side is
nearly flat, and the sutures on the spiral side are radial or slightly curved. There are usually five chambers in the final whorl, but individuals with four were
also found. Often the final chamber is much larger than the penultimate
chamber. The aperture is arched slightly and bordered by a rim or a narrow
plate. The wall is coarsely cancellate.
Similar species: Neogloboquadrina dutertrei is not as distinctly cancellate,
and the chambers do not increase as rapidly in size as those of Globorotaloides
hexagona. Also see G. variabilis. |
Natland,M.L. (1938):
New species of Foraminifers from off the West Coast of North America and from the later Tertiary of the Los Angeles basin . Scripps Inst. Oceanogr. Bull. Tech. Ser. Vol. 4(5) p. 137-164
Srinivasan,M.S. (1975):
Middle Miocene Planktonic Foraminifera from the Hut Bay Formation, Little Andaman Island, Bay of Bengal . Micropaleontology Vol. 21(2) p. 133-150
Kennett,J. and Srinivasan,M.S. (1983):
Neogene Planktonic Foraminifera - A Phylogenetic Atlas.
Vincent,E. and Toumarkine,M. (1990):
Neogene planktonic foraminifers from the Western Tropical Indian Ocean, Leg 115.
In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 115 Eds: Duncan, R.A..Backman, J.Peterson, L.C. p. 795-836
Chaisson,W.P. and Leckie,R.M. (1993):
High-Resolution Planktonic Foraminifer Biostratigraphy of Site 806, Ontong Java Plateau (Western Equatorial Pacific).
In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 130 Eds: Berger, W.H.Kroenke, L.W..Mayer, L.A..et al. p. 137-178
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