Pseudoglobigerinella bolivariana Petters 1954 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513 | . |
Notice: This catalogue page may contain unedited data.
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Species Pseudoglobigerinella bolivariana Petters 1954 |
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| Diagnosis / Definition: |
Pearson et al. (2006):
DESCRIPTION.
Type of wall: Normal perforate, spinose, high
porosity, reticulate, Clavigerinella-type wall structure,
covered by a thick crust in adult stage.
Test morphology: Test globular, nearly involute,
asymmetrically planispiral in adult stage (juvenile stage
very low trochospiral), slightly lobulate in outline,
chambers globular; in spiral view generally 4 globular, embracing chambers in ultimate whorl, increasing rapidly in size, in terminal stage ultimate chamber overlaps the spiral coil, sutures moderately depressed, straight; in umbilical view 4-5 globular, embracing
chambers, increasing rapidly in size, ultimate chamber much inflated, sutures moderately depressed, straight,
umbilicus small and often covered by ultimate chamber; in edge view chambers globular in shape, slightly embracing, aperture asymmetrically equatorial, varying from a low arch to a high distinctive arch, bordered by an imperforate rim and sometimes by a narrow lip that broadens on both sides towards the center of the coil. Size: Maximum diameter of holotype 0.52 mm, thickness 0.40 mm. |
| Discussion / Comments: |
Pearson et al. (2006):
DISTINGUISHING FEATURES.
Pseudoglobigerinella bolivariana is identified by its compact, nearly involute, globular test, asymmetrical equatorial aperture, and the Clavigerinella-type reticulate wall texture and thickened crust. It is distinguished from Parasubbotina grifinae by having an aperture that extends on to the spiral side.
DISCUSSION.-
Pseudoglobigerinella bolivariana has
long been considered an enigmatic species due to its
equatorial aperture. Blow (1 979) was uncertain of its
generic designation when he placed the species in
'Hastigerina?', emphasizing its homeomorphy with the
Recent species 'Hastigerina siphonifera' (=
Globigerinella siphonifera) which he regarded as derived
from the trochospiral species Globorotalia
(Turborotalia) obesa (Blow, 1979, p. 1178). He regarded
his new species, Globorotalia (Turborotalia) griffinae
Blow 1979, as having an analogous ancestral relationship
with P bolivariana as G. obesa did with H. siphonifera
(i.e., the derivation of planispiral coiling from a low
trochospirally coiled morphotype). Toumarkine and
Luterbacher (1 985) followed Blow in placing
bolivariana in ' Hastigerina' .
Blow selected the holotype and some paratypes
for his new species G. (T) griffinae fiom the same sample (KANE 9 Core 42, 200 cm) from which he also
illustrated bolivariana. His case for regarding griffinae
as ancestral to bolivariana is clear from the SEM
illustrations of the two species (his pl. 150, figs. 1-9) as
they both share a Clavigerinella-type reticulate wall
texture (but see comments under Paragloborotalia
griflnoides regarding other paratypes of griffinae).
Blow also emphasized the general range of morphologic
variation in his illustrations of bolivariana (Blow, 1979,
p. 1178) in morphotypes that are more loosely coiled
with 5 chambers in the ultimate whorl, to the tightly
coiled morphotype with a large inflated ultimate
chamber. Toumarkine and Luterbacher (l 985) illustrated
large inflated morphotypes (their fig. 27.25-28) similar
to the holotype but also illustrated a form (their fig.
27.29) similar to the loosely coiled forms illustrated by
Blow (his pl. 150, figs. 3, 4). Plate 5.14 (this chapter)
shows some of the range of morphologic variation
observed in this species. Of aterest is the considerable
variation in the size of the aperture, from a low arch to a
highly elevated arch.
The derivation of the lineage leading to
Pseudoglobigerinella bolivariana is uncertain, as the species has not been intensively studied in stratigraphic
sections. Weiss (1955) noted the tendency in some
morphotypes ofP bolivariana "towards Globigerinellalike
uncoiling" (1955, p. 309) as did Toumarkine and
Luterbacher (their fig. 27.29). Blow was struck by the
close homeomorphy with the Recent species Hastigerina
skhonifera (=Globigerinella siphonlfera) and believed
that "both the Neogene and Palaeogene forms have the
same basic globigerinacean wall structure" (Blow, 1979,
p. 1176). However, subsequent studies show that
siphonifera has a bulloides-type wall texture (Hemleben,
and others, 199 1) whereas P bolivariana has a reticulate,
Clavigerinella-type wall texture (this volume), much
different from that ofsiyhonfera. Thus, the two species
exhibit only a gross homeomorphic similarity. Although
Blow placed bolivariana questionably in Hastigerina,
he believed that bolivariana should be placed in a new
genus if it was demonstrated that the two species could
be morphologically separated.
Hillebrandt (1976) considered Globigerina
inaequispira Subbotina (=Parasubbotina inaequispira) as the ancestor of his new species Pseudohastigerina sphaeroidalis (here considered a junior synonym of P. bolivariana). Blow (1979, p. 749) also entertained a
similar idea, in that he believed "that Globorotalia
(Turborotalia) griffinae represents the derivation of an essentially turborotaliid type of coiling pattern.. .from
the morphotypes included in Subbotina inaequispira",
from which he derived P. bolivariana. As discussed
above, there are two sets of morphotypes that Blow
included in his species grfinae. The first set (illustrated
on his pl. 150) appears related to bolivariana in that it
possesses a high porosity reticulate Clavigerinella-type
wall texture like bolivariana. This type of wall texture
also occurs in Parasubbotina eoclava Coxall, Huber, and
Pearson, which is regarded as the ancestral species of
the Clavigerinella lineage (Coxall and others, 2003) and
also in P. inaequispira, particularly in the late early
Eocene (see discussion under P. inaequispira). Thus, it
appears that P. inaequispira gave rise to two planispiral
genera in the late early Eocene, Pseudoglobigerinella
and Clavigerinella.
Pseudoglobigerinella bolivariana is a rare
species except in areas of high productivity, where it
can dominate the planktonic foraminiferal assemblages.
The species was first described by Petters (1 954) from
the same sample as Clavigerinella colombiana (Petters),
which is also considered by us as an indicator of high
productivity. In Ecuador, Stainforth (1948) reported that
bolivariana was frequently associated with radiolarianrich
shales, and Weiss (1 955) recorded it in depauperate
assemblages from Peru that were probably affected by upwelling. The griffinae-bolivariana-colombiana
biofacies may prove of some use in delineating ancient
areas of upwelling.
PHYLOGENETIC RELATIONSHIPS.-
Pseudoglobigerinella
bolivariana was derived from Parasubbotina
griffinae by a more rapid increase in chamber size, the
development of a nearly involute planispiral test, and
an asymmetrical equatorial aperture.
GEOGRAPHIC DISTRIBUTION.-
identified only in middle Eocene low latitude upwelling areas.
STABLE ISOTOPIC PALEOBIOL0GY.-
No data available. |
| Systematics: |
35
Ordo Foraminiferida
Superfamilia Globigerinaceae
Familia Globigerinidae
Genus Pseudoglobigerinella
Species Pseudoglobigerinella bolivariana
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| Synonym list: |
Pearson et al. (2006):
? 1948 Globigerina wilsoni Cole. - Stainforth : p.117 pl. 26; fig. 1-3 [upper Eocene?, coastal Ecuador]. [Not Cole, 1927.]
1976 Pseudohastigerina globulosa Hillebrandt. - Hillebrandt : p.338 pl. 2; fig. 1a-5b [Globorotalia palmeri Zone, southern
Spain.-Subsequently renamed Pseudohastigerina
sphaeroidalis (Hillebrandt, 1978) due to secondary
homonym status of P. globulosa Hillebrandt]. [Not
Pseudohastigerina wilcoxensis globulosa Gohrbandt
1967, the
1979 Hastigerina? bolivariana Petters. - Blow : p.1177 pl. 150, fig. 1-4 [lower Eocene Zone E7, KANE 9-Core 42,Endeavour Seamount, eastern North Atlantic Ocean];
pl. 251, fig. 8 [Zone E7, Langley Fm., Jamaica]
1985 "Hastigerina" bolivariana Petters. - Toumarkine & Luterbacher : p.127 fig. 27.24a-c (reillustration of holotype);
fig. 27.25-29 [early Middle Eocene, El Datil
Fm., Punta Mosquito, Venezuela]
2006 Pseudoglobigerinella bolivariana Petters. - Pearson et al. : p.98 pl. 5.14; fig. 1-22 (PI. 5.14, Figs. 1-3: new SEMs of holotype of Globigerina wilsoni bolivariana Petters)
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| Specimen: |
Cushman Collection - Smithsonian Museum of Natural History, Washington, D.C., Inventory number: USNM 689637
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| References: |
Stainforth,R.M. (1948):
Applied micropaleontology in Coastal Ecuador . Journ. Paleontol. Vol. 22(2) p. 113-151
Petters,V. (1954):
Tertiary and Upper Cretaceous foraminifera from Colombia, S.A. . Contributions from the Cushman Foundation for Foraminiferal Research Vol. 5 p. 37-41
Weiss,L. (1955):
Foraminifera from the Paleocene Pale Greda Formation of Peru . Journal of Paleontology Vol. 29 p. 1-21
Haque,A.F.M.M. (1956):
The Foraminifera of the Ranikot and the Laki of the Nammal Gorge, Salt Range. Pakistan Geological Survey . Paleontologia Pakistanica Vol. 1 p. 1-300
Samuel,O.. (1972):
New species of planktonic foraminifers from the Paleogene of the west Carpathian in Slovakia (Czechoslovakia) . Zbornik Geologick"ck Vied Západné Karpaty Vol. 17 p. 165-221
Hillebrandt,A. (1976):
Los formainiferos planctonicos, nummulitidos y coccolitoforidos de las zona de Globorotalia palmerae del Cuisiense (Eoceno inferior) en el ES de Espana (Provincias de Murcia y Alicante) . Revista Espanol de Micropaleontologia Vol. 8 p. 323-394
Hillebrandt,A. (1978):
Taxonomic note . Revista Espafiola de Micropaleontologia Vol. 10 p. 337
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
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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