Pseudohastigerina wilcoxensis Cushman & Ponton 1932 from: Toumarkine, M.Luterbacher, H.P. (1985): Paleocene and Eocene Planktic Foraminifera. In: Plankton Stratigraphy p. 87-154 | . |
Notice: This catalogue page may contain unedited data.
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Species Pseudohastigerina wilcoxensis Cushman & Ponton 1932 |
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| Diagnosis / Definition: |
Pearson et al. (2006):
DESCRIPTION.
Type of wall: Smooth, normal perforate.
Test morphology: Test planispiral, compressed,
tightly coiled, involute, oval in outline, lobulate,
chambers, inflated, globular; in umbilical view 6-7
chambers in ultimate whorl, increasing rapidly in size,
sutures slightly depressed, straight to slightly curved,
umbilicus small, circular in shape; in edge view primary
aperture equatorial, symmetric to slightly asymmetric,
a circular high arch bordered by a narrow lip, bipartite
apertures sometimes present on ultimate chamber, test
compressed with a rounded periphery, chambers
globular, peripheral margin perforate.
Size: Maximum diameter of holotype 0.17 mm,
thickness 0.09 mm. |
| Discussion / Comments: |
Toumarkine & Luterbacher (1985):
The small tests are biumbilicate, planispiraly coiled and evolute. In lateral view, the periphery is rounded, although in some specimens it has a tendency to become subacute.
Van Eijden & Smit (1991):
Remarks. P. wilcoxensis was found only in Sample 121-752A-13X-2, 110-115 cm.
Pearson et al. (2006):
DISTINGUISHING FEATURES.-
Pseudohastigerina wilcoxensis is characterized by its planispiral, smooth-walled
test, inflated globular chamber that increase
rapidly in size. The aperture may be a single equatorial
opening or matched bipartite openings. Whether single
or paired, they are symmetrically positioned with respect
to the axial periphery, although slight asymmetry may
occur in some specimens.
DISCUSSION.-
The concept of Pseudohastigerina
wilcoxensis according to Berggren and others (1967)
included morphotypes with an asymmetic aperture that
extended extraumbilically over the axial periphery onto
the spiral side to the trace of the spiral suture. These
morphotypes contrast with other morphotypes where the
aperture assumes an equatorial symmetric position, the
test becomes planispiral and biumbilicate, and the
aperture extends into the umbilicus on both sides. They
also pointed out that the latter morphotypes often
developed a bipartite division of the aperture at the axial
periphery with paired symmetrical apertures present on
both sides ofthe test. The asymmetric morphotypes were
included in P. wilcoxensis to emphasize the transitional
morphology between the proposed trochospiral ancestral
species, Globanomalina chapmani (Parr, 1938), where
the aperture does not extend onto the dorsal side. They
emended the genus Pseudohastigerina, Banner and
Blow, 1959 (type species Pseudohastigerina micra
[Cole], 1927) to include the planispiral to slightly
asymmetric morphotypes. Although Pseudohastigerina
was originally described as having a planispiral test with
an equatorial aperture that extended into the umbilicus
on both sides, Banner and Blow emphasized the presence
of asymmetrical imperforate portici, which they believed
indicated a phylogenetic relationship with certain planktonic genera of the Cretaceous (e.g., Hedbergella,
Globigerinelloides). Blow (1 979) followed the concept
of Pseudohastigerina set forth by Berggren and others
(1967) and emended the genus to include tests with
asymmetric to symmetric equatorial apertures and
bipartite apertures. He drew (arbitrarily) the boundary
between Globorotalia (=Globanomalina) and
Pseudohastigerina "at the point where the primary
aperture opens dorsally in direct continuation of the trace
of the spiral suture" where " a true planispiral coiling-mode
can be said to have been attained' (p. 1060). The
apertural lip was said (p. 1179) not to be a portical
structure and that the genus was confined to the
Paleogene. But Blow (1 979) only provisionally accepted
Pseudohastigerina as a valid genus because he was
unsure of morphologic criteria that could be used to
separate this genus from other planispiral genera in the
Neogene (e.g., Hastigerina).
Using this definition for separating
Pseudohastigerina from Globanomalina, Blow placed
illustrations of two specimens identified by Berggren
and others (1967) as P wilcoxensis (text-fig. 2, d-e, p-r)
in synonomy with Globanomalina chapmani because
the apertures, although they extended slightly over the
axial periphery, did not open into the spiral suture. Blow
also placed Globanomalina luxorensis (Nakkady, 1950)
in synonymy with G. chapmani as did Berggren and
others (1967). Speijer and Samir's (1 997) study of the
Globanomalina-Pseudohastigerina lineage in the
circum-Mediterrean region recognized Nakkady's
species and noted that its first common occurrence was
associated with the negative ò13C shift in Zone El and
emphasized its utility for biostratigraphic purposes. We
concur with Speijer and Samir in that G. luxorensis can
be separated from G. chapmani on the basis of a rounded
axial periphery and an equatorial aperture that does not
open into the trace of the spiral suture. And we concur with Speijer and Samir's identification of text-fig. 2, d-e,
p-r in Berggren and others, 1967 (the illustrations
that Blow had identified as G. chapmani) as G.
luxorensis. The study by Speijer and Samir has helped
clarify the concept of G. luxorensis, which up to this
point had been poorly known, being identified only in
Egyptian deposits; indeed, Olsson and others (1999)
still included this species as a junior synonym of G.
chapmani. Nevertheless, Olsson and others (1999)
pointed out that the lineage leading to Pseudohastigerina
involved Globanomalina imitata (Subbotina, 1953) and
Globanomalina ovalis (Haque, 1956) rather than G. chapmani. Speijer and Samir (l 997) considered G.
ovalis a junior synonym of G. luxorensis and regarded
G. chapmani as ancestral to G. luxorensis. See
discussion under G. luxorensis for details on the
Pseudohastigerina lineage.
PHYLOGENETIC RELATIONSHIPS.-
Pseudohastigerina
wilcoxensis evolved from Globanomalina
luxorensis by a migration of the aperture over the axial
periphery to the trace of the spiral suture, thereby
developing an asymmetric planispiral test in early forms
of P. wilcoxensis. In later forms of P. wilcoxensis the
test becomes symmetrically planispiral and biumbilicate.
The attainment of a planispiral test also leads to the
development of symmetrically opposed bipartite
apertures in some morphotypes ofthe species. Bipartite
apertures are also seen in later species of
Pseudohastigerina.
STRATIGRAPHIC RANGE.-
Base of Zone E2 to
Zone E 10.
GEOGRAPHIC DISTRIBUTION.-
Global in mid to
high latitudes.
STABLE ISOTOPE PALEOBIOL0GY.-
No data
available. |
| Systematics: |
15
Classis Foraminifera
Genus Pseudohastigerina
Species Pseudohastigerina wilcoxensis
32
Ordo Foraminiferida
Familia Hantkeninidae
Genus Pseudohastigerina
Species Pseudohastigerina wilcoxensis
35
Ordo Foraminiferida
Superfamilia Globigerinaceae
Familia Hedbergellidae
Genus Pseudohastigerina
Species Pseudohastigerina wilcoxensis
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| Synonym list: |
Toumarkine & Luterbacher (1985):
1932 Nonion wilcoxensis Cushman & Ponton. - Cushman & Ponton : p.64 pl 8 fig 11 (type reference)
Pearson et al. (2006):
1932 Nonion wilcoxensis Cushman & Ponton. - Cushman & Ponton : p.64 pl. 8; fig. 11a-b [lower Eocene Zone P6, Bashi Fm., Ozark,
Alabama]
p 1953 Globigerinella voluta White. - Subbotina : p.87 pl. 13; fig. 15a-b (not fig. 13a-14b = Pseudohastigerina sharkriverensis);
[lower-middle Eocene Zone of conical
Globorotalia, Sunzha River, Northern Caucasus];
[Not White, 1928]
1959 Nonion wilcoxensis Cushman & Ponton. - Mallory : p.182 pl. 15; fig. 6a-c [lower
Eocene Ynezian Stage, lower Lodo Fm., Media Agua
Creek, California]
1960 Hastigerina eocaenica Berggren. - Berggren : p.85 fig. 1a-2c;
pl. 10, fig. 2a-c;
text-fig. 13-16 [lower Eocene, northwestern
Germany]
p 1967 Pseudohastigerina wilcoxensis Cushman & Ponton. - Berggren et al. : p.278 text-fig. 2.s-v [lower Eocene Zone P6, Bashi Fm., Alabama];
text-fig. 3.2a-5c;
text-fig. 4.2a-5c [lower Eocene Zone P6, Manasquan Fm., New Jersey];
text-fig. 6.la-6c [lower Eocene, Rosnaes Clay Fm., Fiinen, Denmark] (not
text-fig. 2.d-f, m-r =Globanomalina luxorensis)
p 1975 Pseudohastigerina wilcoxensis Cushman & Ponton. - Stainforth et al. : p.243 fig. 99.1-5 [lower Eocene
Zone P6, Lodo Fm., California] (not 6a-c, reillustration of
Berggren and others, 1967, text-fig. 2.p-r =
Globanomalina luxorensis)
p 1979 Pseudohastigerina wilcoxensis Cushman & Ponton. - Blow : p.1193 pl. 159, fig. 8, 9;
pl. 161, fig. 10, 11 (not pl. 252, fig. 1-4 = ?Globanomalina
luxorensis); [middle Eocene Zone P 10, KANE
9-Core 42, equatorial Atlantic Ocean]
1985 Pseudohastigerina wilcoxensis Cushman & Ponton. - Toumarkine & Luterbacher : p.108 fig. 12.9a-c (reillustration of
holotype of Hastigerina eocaenica Berggren);
fig. 12.10a-c (reillustration from literature); fig. 12.1la-b, 12a-c (lla-b, reillustration of Berggren and others, 1967, text-fig. 2.s-t; 12a-c, reillustration of Berggren and others, text-fig. 2.j-l)
1995 Pseudohastigerina wilcoxensis Cushman & Ponton. - Lu & Keller : p.102 pl. 6; fig. 7, 8 [lower
Eocene Zone P6, DSDP Site 577, Shatsky Rise,
northwestern Pacific Ocean]
1997 Pseudohastigerina wilcoxensis Cushman & Ponton. - Speijer & Samir : p.54 pl. 2; fig. 5a-c [lower Eocene, Gebel Aweina,
Egypt, sample PIE = 10 cm]
2006 Pseudohastigerina wilcoxensis Cushman & Ponton. - Pearson et al. : p.429 pl. 14.4; fig. 1-8 (Pl. 13.4, Fig. l, 2: new SEMs of holotype of Nonion
wilcoxensis Cushman and Ponton)
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| Was used in synonym list of: |
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| Specimen: |
Smithsonian Museum of Natural History, Washington, D.C., Inventory number: USNM CC 16214
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| References: |
Cushman,J.A. and Ponton,G.M. (1932):
An Eocene foraminiferal fauna of Wilcox age from Alabama . Contributions from the Cushman Foundation for Foraminiferal Research Vol. 8 p. 51-72
Bandy,O.L. (1949):
Eocene and Oligocene foraminifera from Little Stave Creek, Clarke County, Alabama . Bulletins of American paleontology Vol. 32 p. 1-211
Subbotina,N.N. (1953):
Iskopaemye foraminifery SSSR (Globigerinidy, Khantkenininidy i Globorotaliidy) . Trudy Vsesoyznogo Nauchno-Issledovatel'skogo Geologo-razvedochnogo Instituta (VNIGRI) Vol. 76 p. 296
Mallory,V.S. (1959):
Lower Tertiary Biostratigraphy of the California Coast Ranges. p. 146
Berggren,W.A. (1960):
Some planktonic Foraminifera from the Lower Eocene (Ypresian) of Denmark and northwestern Germany . Stockholm Contribution in Geology Vol. 5 p. 41-108
Gohrbrandt,K.H.A. (1967):
Some new foraminiferal species from the Austrian Eocene . Micropaleontolgy Vol. 13 p. 319-326
Berggren,W.A.; Olsson,R.K. and Reyment,R.A. (1967):
Origin and Development of the Foraminiferal Genus Pseudohastigerina Banner and Blow, 1959 . Micropaleontology Vol. 13 p. 265-288
McKeel,D.R.. and Lipps,J.H. (1975):
Eocene and Oligocene planktonic foraminifera from the central and southern Oregon coast range . Journal of Foraminiferal Research Vol. 5 p. 1-5
Stainforth,R.M.; Lamb,J.L.; Luterbacher,H.P.; Beard,J.H. and Jeffords,R.M. (1975):
Cenozoic planktonic foraminiferal zonation and characteristics of index forms . Paleontological ContributionsArticle 62 p. 425
Blow,W.H. (1979):
The Cainozoic Globigerinida. 3 Vols p. 1413 pp
Toumarkine,M. and Luterbacher,H.P. (1985):
Paleocene and Eocene Planktic Foraminifera.
In: Plankton Stratigraphy p. 87-154
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
Lu,G. and Keller,G. (1995):
Planktic Foraminiferal Faunal Turnovers in the Subtropical Pacific during the Late Paleocene to Early Eocene . Journal of Foraminiferal Research Vol. 25 p. 97-116
Speijer,R.P.. and Samir,A.M.. (1997):
Globanomalina luxorensis, a Tethyan biostratigraphic marker of latest Paleocene global events . Micropaleontology Vol. 43 p. 51-62
Pearson,P.N.; Olsson,R.K.; Hemleben,C.; Huber,B.T. and Berggren,W.A. (2006):
Atlas of Eocene Planktonic Foraminifera. p. 1-513
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