Distinguishing features: Parent taxon (Pulleniatina): Compact streptospiral test with smooth cortical coating and large slit-like aperture This taxon: Like P. primalis but aperture extends onto the periphery of the previous whorl
NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus. They are being edited as the site is developed and comments on them are especially welcome.
Description
Morphology: Test medium,initially trochospiral, later streptospiral, equatorial periphery slightly lobulate, axial periphery broadly rounded, chambers subspherical, about 5 to 6 in the final whorl,increasing slowly in size except for the last chamber, which is abruptly more embracing; sutures weak, on spiral side curved, gently depressed; on umbilical side radial, depressed ; surface smooth, covered with thick cortex, granular on early chambers facing the aperture; umbilicus covered by last chamber; aperture interiomarginal, extraumbilical-umbilical, a rather medium arch along the base of the final chamber extending up to the periphery of the preceding whorl. [Kennett & Srinivasan 1983] Wall type: Non-spinose; Smooth [Aze 2011]
Character matrix
test outline:
Subcircular
chamber arrangement:
Trochospiral
edge view:
Inequally biconvex
aperture:
Umbilical-extraumbilical
sp chamber shape:
Crescentic
coiling axis:
Low
periphery:
N/A
aperture border:
N/A
umb chbr shape:
Subtriangular
umbilicus:
Narrow
periph margin shape:
Broadly rounded
accessory apertures:
None
spiral sutures:
Flush
umb depth:
Shallow
wall texture:
Smooth
shell porosity:
Macroperforate: >2.5µm
umbilical or test sutures:
Flush
final-whorl chambers:
5.0-6.0
N.B. These characters are used for advanced search. N/A - not applicable
Biogeography and Palaeobiology
Geographic distributionTropical to warm subtropical. [Kennett & Srinivasan 1983] Low latitudes [Aze et al. 2011, based on Kennett & Srinivasan (1983)]
[SCOR WG138]
Isotope paleobiologyAze et al. 2011 ecogroup 3 - Open ocean thermocline; based on comparison with other species of the genus. Phylogenetic relationsPu. praecursor represents an intermediate evolutionary stage between Pu. primalis and Pu. obliquiloculata. It is distinguished from Pu. primalis by its aperture, which extends farther onto the periphery than Pu. primalis. [Kennett & Srinivasan 1983]
Geological Range: Last occurrence (top): within N21 zone (1.93-3.10Ma, top in Gelasian stage). Data source: Kennett & Srinivasan 1983 First occurrence (base): within N19 zone (4.37-5.20Ma, base in Zanclean stage). Data source: Kennett & Srinivasan 1983
Plot of occurrence data:
Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
Primary source for this page: Kennett & Srinivasan 1983, p.200
References:
Aze, T. et al. (2011). A phylogeny of Cenozoic macroperforate planktonic foraminifera from fossil data. Biological Reviews. 86: 900-927. gs
Banner, F. T. & Blow, W. H. (1967). The origin, evolution and taxonomy of the foraminiferal genus Pulleniatina Cushman, 1927. Micropaleontology. 13(2): 133-162. gs
Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs
Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs
Pulleniatina praecursor compiled by the pforams@mikrotax project teamviewed: 20-3-2023