Pseudohastigerinadanvillensis (Howe and Wallace).—Blow, 1979:1181 (partim; not pl. 166, figs. 8-10; pl. 253: figs. 10-12.), pl. 159: figs. 6-7, pl. 161: figs. 2-7; pl. 166: figs. 2-10 [middle Eocene Zone P10, KANE 9-Core 42, equatorial Atlantic Ocean]. [Not Howe and Wallace, 1932.]
Taxonomic discussion: Planoglobanomalinapseudoalgeriana n. sp. is the type species for the new genus Planoglobanomalina. Blow referred morphotypes from a North Atlantc core to the Eocene/Oligocene planispiral genus Pseudohastigerina and stated that the genus had a polyphyletic origin, first appearing at the beginning of the Eocene and again in the early Eocene Zone P9. We believe that Blow’s observations are correct in as much as we have observed a similar relationship in Zone E6 in the western North Pacific ODP Hole 865B and are the basis for this new species. Hillebrandt (1976) was first to illustrate this species (identified as P. micra) in Zone E7 from southeastern Spain. [Olsson & Hemleben 2006]
Distinguishing features: Parent taxon (Planoglobanomalina): Planispiral, compressed, loosely coiled, numerous chambers in final whorl, last 1-3 chambers uncoiling. Aperture equatorial, oval-shaped with broad lip. This taxon: Test loosely coiled, evolute, and compressed; 9-10 chambers in the final whorl, last three chambers showing a trend towards uncoiling.
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
Diagnostic characters: The most distinguishing feature of Planoglobanomalinapseudoalgeriana n. sp. is the remarkable homeomorphy it shows with the upper Aptian planktonic foraminifer Globigerinelloidesalgerianus Cushman and ten Dam (1948) from which its name is derived. The test of P. pseudoalgeriana n. sp. is loosely coiled, evolute, and much compressed with 9-10 chambers in the ultimate whorl and with the last three chambers showing a trend towards uncoiling. Globanomalina is trochospiral, tightly coiled, has few chambers in the ultimate whorl, and an extraumbilical aperture confined to the umbilical side. [Olsson & Hemleben 2006] Morphology: Test asymmetrical to fully planispiral, compressed, loosely coiled, evolute, oval in outline, chambers compressed, distinctly elongate; inner spire of chambers visible due to loose coiling, 9-10 chambers in ultimate whorl, increasing gradually in size last three chambers in ultimate whorl arranged in an uncoiling trend, sutures slightly depressed, straight to moderately curved, umbilicus moderate in size, circular in shape, apertural lips of ultimate chamber and previous chambers fuse to form a somewhat broad shelf that extends around the umbilicus, relict apertures present where apertural lips are not completely fused; in edge view primary aperture equatorial, asymmetric, an oval-shaped opening bordered by a broad lip, test much compressed with a pinched periphery which gives the chambers an ogyval shape. [Olsson & Hemleben 2006] Wall type: Smooth, normal perforate. Well-preserved specimens show smooth calcite overgrowths on the umbilical shoulders of chambers and similar irregular, discontinuous smooth bands on the test periphery. [Olsson & Hemleben 2006]
Character matrix
test outline:
Ovate
chamber arrangement:
Planispiral
edge view:
Compressed
aperture:
Equatorial
sp chamber shape:
Petaloid
coiling axis:
Very low
periphery:
N/A
aperture border:
Thick flange
umb chbr shape:
Petaloid
umbilicus:
Wide
periph margin shape:
Narrowly rounded
accessory apertures:
Intralaminal
spiral sutures:
Weakly depressed
umb depth:
Shallow
wall texture:
Smooth
shell porosity:
Finely Perforate: 1-2.5µm
umbilical or test sutures:
Weakly depressed
final-whorl chambers:
9-10
N.B. These characters are used for advanced search. N/A - not applicable
Biogeography and Palaeobiology
Geographic distributionThe occurrence of this species in southeastern Spain, Tanzania, North Atlantic Ocean, and at ODP Hole 865B, western North Pacific Ocean suggests that it was widespread in low to mid latitudes. [Olsson & Hemleben 2006]
Aze et al. 2011 summary: Low to middle latitudes; based on Olsson & Hemleben (2006) Isotope paleobiologyNo data available. [Olsson et al. 1999] Aze et al. 2011 ecogroup 2 - Open ocean mixed-layer tropical/subtropical, without symbionts; based on comparison with other species of the genus. Phylogenetic relationsPlanoglobanomalinapseudoalgeriana n. sp. evolved from Globanomalinaplanoconica in Zone E6. [Olsson & Hemleben 2006]
Most likely ancestor: Globanomalina planoconica - at confidence level 4 (out of 5). Data source: Olsson & Hemleben 2006, fig 14.1.
Biostratigraphic distribution
Geological Range: Notes: Zone E6 to Zone E7b. [Olsson & Hemleben 2006 - but corrected following zonal definition change of Wade et al. 2011] Last occurrence (top): in upper part of E7b subzone (80% up, 46.2Ma, in Lutetian stage). Data source: Olsson & Hemleben 2006, fig 14.1 First occurrence (base): in lower part of E6 zone (20% up, 50.6Ma, in Ypresian stage). Data source: Olsson & Hemleben 2006, fig 14.1
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.
Grey shading between taxa indicates intergrading species within an anagenetic lineage (data from
Lamyman et al. 2026).
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
Taxon plotted: Planoglobanomalina pseudoalgeriana, synonyms included - Pseudohastigerina pseudoalgeriana;
Primary source for this page: Olsson & Hemleben 2006 - Eocene Atlas, chap. 14, p. 419
References:
Blow, W. H. (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea). E. J. Brill, Leiden. 2: 1-1413. gs
Cushman, J. A. & Ten Dam, A. (1948). Globigerinelloides, a new genus of the Globigerinidae. Contributions from the Cushman Laboratory for Foraminiferal Research. 24(2): 42-43. gs
Hillebrandt, A. , von (1976). Los foraminiferos planctonicos, nummulitidos y coccolitoforidos de la zona de Globorotalia palmerae del Cuisiense (Eoceno inferior) en el SE de Espana, (Provincias de Murcia y Alicante. Revista Española de Micropaleontología. 8(3): 323-394. gsO
Howe, H. V. & Wallace, W. E. (1932). Foraminifera of the Jackson Eocene at Danville Landing on the Ouachita, Catahoula Parish, Louisiana. Bulletin of the Geological Survey of Louisiana. 2: 1-118. gs
Olsson, R. K. & Hemleben, C. (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene Globanomalina, Planoglobanomalina n. gen and Pseudohastigerina. In, Pearson, P. N., Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication . 41(Chap 14): 413-432. gsO
Planoglobanomalina pseudoalgeriana compiled by the pforams@mikrotax project teamviewed: 5-10-2026
Eocene_Atlas_pl14-2_fig5 10 11.jpg
Eocene_Atlas_pl14-2_fig7 15.jpg
Eocene_Atlas_pl14-2_fig6-8-9-16.jpg
Eocene_Atlas_pl14-2_fig12-14-19.jpg
Eocene_Atlas_pl14-2_fig17-20.jpg
Eocene_Atlas_pl14-2_fig18.jpg
Eocene_Atlas_pl14-2_fig5 10 11.jpg
Eocene_Atlas_pl14-2_fig7 15.jpg
Eocene_Atlas_pl14-2_fig6-8-9-16.jpg
Eocene_Atlas_pl14-2_fig12-14-19.jpg
Eocene_Atlas_pl14-2_fig17-20.jpg
Eocene_Atlas_pl14-2_fig18.jpg
holotype: P. pseudoalgeriana
