pforams@mikrotax - Globigerinatheka index

Citation: Globigerinatheka index (Finlay 1939)

Synonyms:

Globigerinoides index Finlay, 1939:125 (partim), pl. 14: figs. 85-88 [middle Eocene, Bortonian stage, Hampden Section, New Zealand].—Hornibrook, 1958: pl. 1: figs. 11-13 (redrawn holotype), fig. 14 (redrawn paratype).
Globigerapsis index (Finlay).—Blow and Banner, 1962: pl. 15 (partim): fig. G [middle Eocene, Kilwa district, Tanganyika] (not fig. H = G. kugleri).—Quilty, 1969, text-fig. 7, no. 42-48 [fide Bolli, 1972]. —Soldaini, 1970:67, pl. 5: figs. 1, 5 [upper Eocene Globigerapsis semiinvoluta Zone, Mor 1Well, Hungary].—Baumann, 1970: pl. 1: figs. 12a-c [middle Eocene Globigerapsis subconglobata Zone, Bottaccione Section, Gubbio, central Italy]. —Samanta, 1970: pl. 2: fig. 17, not fig. 16 [middle Eocene
Orbulinoides beckmanni Zone, Lakhpat, Cutch. India].— Postuma, 1971:136, figs. on p. 137 [Eocene, Hampden Section, New Zealand].—Toumarkine, 1971: pl. 3: ?figs. 11, 12 [middle Eocene Globorotalia lehneri /Hantkenina dumblei Zone, Halimba borehole, Bakony Mountain, Hungary].—Blow, 1979: pl. 27: figs. 1, 2; pl. 192: fig. 1 [middle Eocene Zone P13, Kilwa Area, Tanzania]; pl. 174: ?fig. 1, figs. 2, 3, 4, 6, 8 [middle Eocene Zone P11, Kilwa Area, Tanzania]; pl. 181: fig. 1; pl. 183: ?figs. 1, 2 ; pl. 186: figs. 2, 3 [middle Eocene Zone P11, DSDP Site 19, Rio Grande Rise, South Atlantic Ocean].— Krasheninnikov and Basov, 1983: pl. 7: figs. 2-3, [upper Eocene, DSDP Site 512, Maurice Ewing Bank, South Atlantic Ocean]; pl. 7: figs. 4-5 [upper Eocene, DSDP Site 511, Falkland Plateau, South Atlantic Ocean].
?Globigerapsis index (Finlay).—Samuel and Salaj, 1968, text-fig. 38 [upper Eocene ?Globigerina officinalis Zone, Magura Flusch, Bystrica Unit, Kochanovce borehole, Slovakia].
Globigerinatheka (Globigerapsis) index index (Finlay).— Jenkins, 1971:187-188, pl. 22: figs. 641-643 (redrawn holotype), fig. 644 (redrawn paratype), fig. 645 [middle Eocene Globigerinatheka (Globigerapsis) index index Zone, Bortonian stage, Hampden Section, New Zealand].
Globigerinatheka index index (Finlay).—Bolli, 1972:124 (partim), text-figs. 51-57 (redrawn Finlay’s type specimens), not text-figs. 63-64; pl. 1: ?fig. 1, figs. 3-4, not figs. 6-7 = G. subconglobata [middle Eocene Globigerinatheka subconglobata subconglobata Zone, Possagno Section, northern Italy].—Fleisher, 1974: pl. 8: fig. 6 [middle Eocene Zone P11, DSDP Site 220, Arabian Sea].—McKeel and Lipps, 1975: pl. 3: figs. 5a-c; pl. 5: figs. 1a-c [upper Eocene, Bastendorff Fm., Oregon Coast Range].—Toumarkine, 1975: pl. 4: figs. 6, 7 [upper Eocene Globigerinatheka semiinvoluta Zone, DSDP Site 305, Shatsky Rise, northwest Pacific Ocean].— Toumarkine, 1978: pl. 5:, figs. 3-5, 7-9, ?figs. 1, 6 [fig. 3, middle Eocene Orbulinoides beckmanni Zone; figs. 2-9, middle Eocene Truncorotaloides rohri Zone, DSDP Site 363, South Atlantic Ocean].—Toumarkine, 1983: pl. 19: figs. 20-21 [upper Eocene Globigerinatheka semiinvoluta Zone, DSDP Site 305, Shatsky Rise, northwest Pacific Ocean]; figs. 22-24 [middle Eocene Truncorotaloides rohri Zone, DSDP Site 363, South Atlantic Ocean].—Poag and Commeau, 1995: pl. 5: fig. 27 [upper Eocene Zone P15, Exmore core, Salisbury Embayment, Virginia-Maryland].
Globigerinatheka index (Finlay).—Stainforth and others, 1975: figs. 56.1, 3, ?fig. 56.2 (from Bolli, 1972); fig. 56.6 (from Blow and Banner, 1962).—Snyder and Waters, 1985: pl. 5: fig. 3 [DSDP Hole 548A, Goban Spur, eastern North Atlantic Ocean]; ?fig. 4 [DSDP Hole 548A, Goban Spur, eastern North Atlantic Ocean]. —Coccioni and others, 1988: pl. 1: figs. 11, 12 [upper Eocene Zone P16, Massignano Section, Marche, central Italy]. —Nocchi and others, 1988: pl. VI: figs. 8a,b [upper Eocene Zone P16, Section PMI, Umbria, central Italy]. —Premoli Silva and Spezzaferri, 1990: pl.1: figs. 8b,c [upper Eocene Zones P15/P17, ODP Hole 709C, Indian Ocean].—Huber, 1991:440, pl. 7: fig. 17, ?fig. 22 [middle Eocene, ODP Hole 738B, Kerguelen Plateau, Indian Ocean]. —Nocchi and others, 1991: pl. 4: ?figs. 17-19 [middle Eocene Zone P11, ODP Hole 702B, South Atlantic Ocean]; figs. 20-22 [middle Eocene Zone P12, ODP Hole 702B, South Atlantic Ocean].—Van Eijden and Smit, 1991: pl. 3: fig. 8, ?fig. 7 [middle Eocene Zones P13-P14, ODP Hole 752A, Broken Ridge, Indian Ocean].—Berggren, 1992: pl. 3 (partim): figs. 10-11 (not fig. 9 = G. luterbacheri) [middle Eocene, ODP Hole 748B, (figs. 9-11, 16H-5, 40-44 cm), Kerguelen Plateau, Indian Ocean].
Globigerina index (Finlay).—Stott and Kennett, 1990:559, pl. 7: fig. 8 [middle Eocene Zone AP6, ODP Hole 690B, Maud Rise, Antarctic Ocean].
Globigerinatheka sp. cf. G. index (Finlay).—Van Eijden and Smit, 1992: pl. 3 (partim): fig. 4, ?fig. 5 [fig. 4, lower middle Eocene Zones P10-P12, ODP Hole 752A; fig. 5, middle Eocene Zones P13-P14, ODP Hole 752A, Broken Ridge, Indian Ocean] (not fig. 9).
?Globigerinatheka index (Finlay).—V an Eijden and Smit, 1991: pl. 3: fig. 6 [middle Eocene Zones P13-P14, ODP Hole 752A, Broken Ridge, Indian Ocean].
Globigerinoides macrostoma Hagn, 1956:173, pl. 16: fig. 11a-b [upper Eocene, Varignano, Lake Garda, northern Italy]. Globigerinoides conglobatus (Brady). —Shutskaya, 1958: pl. 2: fig. 1 [upper Eocene, fig. 1, Khieu River, Nalchik region], fig. 2 [Belaya River, Maikop district, Caucasus]. [Not Brady, 1879.]
Globigerapsis aff. semiinvoluta (Keijzer). —Soldaini, 1970:67, pl. 5: figs. 4a,c [upper Eocene Globigerapsis semiinvoluta Zone, Mo_r 1Well, Hungary]. [Not Keijzer, 1945.]
Globigerinatheka mexicana mexicana (Cushman).—Nishi and Chaproniere, 1994: pl. 2: figs. 14-15, ?fig. 13 [upper Eocene Zones 15-16, DSDP Hole 841B, south-west Pacific Ocean]. [Not Cushman, 1925.]
Not Globigerinoides index Finlay.—Beckmann, 1953: pl. 25: fig. 14 [upper Eocene, Oceanic Fm., Barbados] (= G. semiinvoluta).—Hagn, 1956:172, pl. 16: figs. 6-8 (= G. tropicalis).
Not Globigerapsis index (Finlay).—Bolli, 1957:165, pl. 36: figs. 14a,b-18b (= G. subconglobata).—Todd, 1966: pl. 2: figs. 1a-1c (= G. curryi).—Samuel and Salaj, 1968: pl. 21: figs. 2a-c (= G. tropicalis).—Blow, 1969: pl. 27: figs. 1-2 (= G. korotkovi). —Samanta, 1970: pl. 2: fig. 16 (= G. barri).—Blow, 1979: pl. 174: figs. 5, 7.—Krasheninnikov and Basov, 1983: pl. 7: fig. 1.
Not Globigerinatheka index (Finlay).—Stainforth and others, 1975: fig. 56.4 [from Blow and Banner, 1962]; figs. 56.5,7,9 [from Bolli, 1972]; figs. 56.8a-b [from Blow, 1969].
Not Globigerinatheka index index (Finlay).—Berggren, 1992: pl. 3: figs. 5-6 (= G. tropicalis); ?fig. 8 (= G. korotkovi) [middle Eocene, ODP Hole 748B, Kerguelen Plateau, Indian Ocean].—Nishi and Chaproniere, 1994: pl. 2: figs. 4-6 (= G. tropicalis), figs. 22-24 (= G. luterbacheri) [upper Eocene Zones P15-16, DSDP Hole 841B, south-west Pacific Ocean].

Taxonomic discussion: At high latitudes (including the type locality), specimens of G. index with typically incised sutures commonly display poorly developed secondary spiral apertures or are even devoid of them. Even though the overall shape, which recalls some Neogene Globigerinoides, and the incised sutures differentiate G.
index from all other globigerinathekids, this species has frequently been misidentified (see synonymy list). Hagn (1956) described Globigerinoides macrostoma as a new species. According to Bolli (1972), G. macrostoma should be considered as a junior synonym of G. index, with which it shares the same features: Hagn’s figures of the specimen he identified as G. index is in fact attributable to G. tropicalis, and he created the new species G. macrostoma for the ‘true G. index’.
Judging from the original figures, the paratype of G. index illustrated by Finlay in his fig. 87 seems to exhibit some similarities in general shape with G. korotkovi Keller, but redrawing of Finlay’s paratype by Hornibrook (1958) shows well the incised sutures lacking in Keller’s species. [Premoli Silva et al. 2006]

Distinguishing features:
Parent taxon (Globigerinatheka): Medium to large, subspherical to spherical tests; multiple secondary apertures, frequently covered by bullae.
This taxon: Well defined incised sutures and large, high-arched, primary aperture located above the suture between the first two chambers of the final whorl.

Description

Globigerinatheka index is distinguished by its well defined incised sutures and large, high-arched, primary aperture located above the suture between the first two chambers of the final whorl. This taxon differs from G. tropicalis by its semicircular, rimmed apertures and deeply incised distinct sutures. [Premoli Silva et al. 2006]

Test slightly elongate, subrectangular in outline, rather compact, broadly rounded and subrectangular in side view; early chambers poorly visible, arranged in a low trochospire of possibly 2 to 3 whorls, with the last whorl consisting of 3 inflated chambers at least twice as large as earlier chambers, antepenultimate and penultimate chambers of almost equal size separated by a vertical suture in umbilical view, the last chamber making almost one-half of the whole test; sutures of the inner chambers poorly visible, possibly straight or slightly curved, sutures in the last whorl distinct, deeply incised, straight and radial; primary aperture, umbilical, a rather high and large, symmetrical arch at the base of the last chamber, frequently bordered by a thick lip, two medium-sized, semicircular arched, secondary apertures at the base of the last chamber above the sutures of previous chambers. Bullae are not common. [Premoli Silva et al. 2006]

Spinose, cancellate, frequently encrusted, with mainly cylindrical pores, about 4 to 5 mm in diameter. [Premoli Silva et al. 2006]

Dimensions for population range from 0.35 mm to 0.55 mm. Diameter of the holotype 0.4 mm. [Premoli Silva et al. 2006]

Biogeography and Palaeobiology

Cosmopolitan, but more abundant in high latitudes. [Premoli Silva et al. 2006]
Aze et al. 2011 summary: Cosmopolitan; based on Premoli Silva et al. (2006)

Stable isotope data indicates depleted δ18O and enriched δ13C values suggesting a mixed layer habitat, comparable to co-occurring Acarinina, but possibly with a greater tendency to sink at gametogenesis (Boersma and others, 1979; Pearson and others, 1993, 2001). This paleohabitat is supported by boron isotope data (Pearson and Palmer, 1999). [Premoli Silva et al. 2006]
Aze et al. 2011 ecogroup 1 - Open ocean mixed-layer tropical/subtropical, with symbionts. Based on very heavy _¹³C and relatively light _¹⁸O. Sources cited by Aze et al. 2011 (appendix S3): Boersma et al. (1979); Pearson et al. (2001a); Pearson & Palmer (1999)

There is a general agreement that G. index is related to G. tropicalis, which is its tropical equivalent according to Blow (1969) and Jenkins (1971). [Premoli Silva et al. 2006]

Biostratigraphic distribution

Geological Range:
Notes: Described from the middle Eocene of New Zealand, the extinction of G. index has been used for approximating the upper boundary of the Eocene at the high southern latitudes (Jenkins, 1971). It appears in upper E9. At middle latitudes G. index decreases in abundance in mid Zone E15 and disappears at the E15/E16 boundary (Berggren and Pearson, Chapter 2, this volume). [Premoli Silva et al. 2006]
The LAD of Globigerinatheka index marks the base of zone E16 / top of E15 (Wade et al. 2011)
Last occurrence (top): at top of E15 zone (100% up, 34.7Ma, in Priabonian stage). Data source: zonal marker (Wade et al. 2011)
First occurrence (base): in upper part of E9 zone (80% up, 43.4Ma, in Lutetian stage). Data source: Premoli Silva et al. 2006 f7.1

Primary source for this page: Premoli Silva et al. 2006 - Eocene Atlas, chap. 7, p. 183

References:

Baumann, P. (1970). Mikropalaentologische und stratigraphische Untersuchungen der obereozaenen-oligozaenen Scaglia im zentralen Apennin (Italien). Eclogae Geologicae Helvetiae. 63: 1133-1211. gs

Beckmann, J. P. (1953). Die Foraminiferen der Oceanic Formation (Eocaen-Oligocaen) von Barbados, Kl. Antillen. Eclogae Geologicae Helvetiae. 46(2): 301-412. gs O

Berggren, W. A. (1992). Paleogene planktonic foraminifer magnetobiostratigraphy of the southern Kerguelen Plateau (sites 747-749). Proceedings of the Ocean Drilling Program, Scientific Results. 120: 551-568. gs

Blow, W. H. & Banner, F. T. (1962). The mid-Tertiary (Upper Eocene to Aquitanian) Globigerinaceae. In, Eames, F. E., Banner, F. T., Blow, W. H. & Clarke, W. J. (eds) Fundamentals of mid-Tertiary Stratigraphical Correlation. Cambridge University Press, Cambridge 61-151. gs

Blow, W. H. (1969). Late middle Eocene to Recent planktonic foraminiferal biostratigraphy. In, Bronnimann, P. & Renz, H. H. (eds) Proceedings of the First International Conference on Planktonic Microfossils, Geneva, 1967. E J Brill, Leiden 380-381. gs

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

Boersma, A., Shackleton, N. J., Hall, M. A. & Given, Q. (1979). Carbon and oxygen isotope records at DSDP site 384 (North Atlantic) and some Paleocene paleotemperatures and carbon isotope variations in the Atlantic Ocean. Initial Reports of the Deep Sea Drilling Project. 43: 695-717. gs

Bolli, H. M. (1957a). Planktonic foraminifera from the Eocene Navet and San Fernando formations of Trinidad. In, Loeblich, A. R. , Jr., Tappan, H., Beckmann, J. P., Bolli, H. M., Montanaro Gallitelli, E. & Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin . 215: 155-172. gs

Bolli, H. M. (1972b). The genus Globigerinatheka Bronnimann. Journal of Foraminiferal Research. 2(3): 109-136. gs O

Brady, H. B. (1879). Notes on some of the rerticularian rhizopoda of the "Challenger" Expedtion. II Additions to the knowledge of porcellaneous and hyaline types. Quarterly Journal of Microscopical Science. 19: 261-299. gs

Coccioni, R., Monaco, P., Monechi, S., Nocchi, M. & Parisi, G. (1988). Biostratigraphy of the Eocene-Oligocene boundary at Massignano, (Ancona, Italy). In, Premoli Silva, I., Coccioni, R. & Montanari, A. (eds) The Eocene-Oligocene Boundary in the Marche-Umbria Basin (Italy). International Subcommission on Paleogene Stratigraphy, Ancona 59-80. gs

Cushman, J. A. (1925d). New foraminifera from the Upper Eocene of Mexico. Contributions from the Cushman Laboratory for Foraminiferal Research. 1(1): 4-9. gs

Finlay, H. J. (1939b). New Zealand foraminifera: Key species in stratigraphy - no. 2. Transactions of the Royal Society of New Zealand. 69(1): 89-128. gs

Fleisher, R. L. (1974a). Cenozoic planktonic foraminifera and biostratigraphy, Arabian Sea, Deep Sea Drilling Project, Leg 23A. Initial Reports of the Deep Sea Drilling Project. 23: 1001-1072. gs O

Hagn, H. (1956). Geologische und Palaontologische untersuchungen im Tertial des Monte Brione und seiner Umgebung. Palaeontographica Abteilung A Palaeozoologie Stratigraphie. 107(3-6): 67-210. gs

Hornibrook, N. d. B. (1958). New Zealand Upper Cretaceous and Tertiary foraminiferal zones and some overseas correlations. Micropaleontology. 4: 25-38. gs

Huber, B. T. (1991c). Paleogene and Early Neogene Planktonic Foraminifer Biostratigraphy of Sites 738 and 744, Kerguelen Plateau (Southern Indian Ocean). Proceedings of the Ocean Drilling Program, Scientific Results. 119: 427-449. gs

Jenkins, D. G. (1971). New Zealand Cenozoic Planktonic Foraminifera. New Zealand Geological Survey, Paleontological Bulletin. 42: 1-278. gs

Keijzer, F. G. (1945). Outline of the geology of the eastern part of the Province of Oriente, Cuba (E of 76° W.L.), with notes on the geology of other parts of the island. Publicaties uit het Geographisch en uit het Mineralogisch-Geologisch Instituut der Rijksuniversiteit te Utrecht, Physiographisch-Geologische Reeks, ser II,. 6: 1-239. gs

Krasheninnikov, V. A. & Basov, I. A. (1983). Stratigraphy of Cretaceous sediments of the Falkland Plateau based on planktonic foraminifers, Deep Sea Drilling Project, Leg 71. Initial Reports of the Deep Sea Drilling Project. 71: 789-820. gs

McKeel, D. R. & Lipps, J. J. (1975). Eocene and Oligocene planktonic foraminifera from the Central and Southern Oregon Coast Range. Journal of Foraminiferal Research. 5(4): 249-269. gs O

Nishi, H. & Chaproniere, G. C. H. (1994). Eocene-Oligocene subtropical planktonic foraminifers at Site 841,. Proceedings of the Ocean Drilling Program, Scientific Results. 135: 245-266. gs

Nocchi, M., Parisi, G., Monaco, P., Monechi, S. & Madile, M. (1988b). Eocene and early Oligocene micropaleontology and paleoenvironments in SE Umbria, Italy. Palaeogeography Palaeoclimatology Palaeoecology. 67: 181-244. gs

Nocchi, M., Amici, E. & Premoli Silva, I. (1991). Planktonic foraminiferal biostratigraphy and paleoenvironmental interpretation of Paleogene faunas from the subantarctic transect, Leg 114. Proceedings of the Ocean Drilling Program, Scientific Results. 114: 233-273. gs

Pearson, P. N. & Palmer, M. R. (1999). Middle Eocene seawater pH and atmospheric carbon dioxide concentrations. Science. 284: 1824-1826. gs

Pearson, P. N., Shackleton, N. J. & Hall, M. A. (1993). Stable isotope paleoecology of middle Eocene planktonic foraminifera and multi-species isotope stratigraphy, DSDP Site 523, South Atlantic. Journal of Foraminiferal Research. 23: 123-140. gs

Poag, C. W. & Commeau, J. A. (1995). Paleocene to middle Miocene planktic foraminifera of the southwestern Salisbury Embayment, Virginia and Maryland: Biostratigraphy, allostratigraphy, and sequence stratigraphy. Journal of Foraminiferal Research. 25: 134-155. gs

Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs

Premoli Silva, I. & Spezzaferri, S. (1990). Paleogene planktonic foraminifer biostratigraphy and paleoenvironmental remarks on paleogene sediments from Indian Ocean sites, Leg 115. Proceedings of the Ocean Drilling Program, Scientific Results. 115: 277-314. gs

Premoli Silva, I., Wade, B. S. & Pearson, P. N. (2006). Taxonomy, biostratigraphy, and phylogeny of Globigerinatheka and Orbulinoides. 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 7): 169-212. gs O

Quilty, P. G. (1969). Upper Eocene planktonic foraminiferida from Albany, Western Australia. Journal of the Royal Society of Western Australia. 52(2): 41-58. gs

Samuel, O. & Salaj, J. (1968). Microbiostratigraphy and Foraminifera of the Slovak Carpathian Paleogene. Geologicky Ustav Dionyza Stura, Bratislava. 1-232. gs

Snyder, S. W. & Waters, V. J. (1985). Cenozoic planktonic foraminiferal biostratigraphy of the Goban Spur Region, Deep Sea Drilling Project Leg 80. Initial Reports of the Deep Sea Drilling Project. 80: 439-472. gs

Stainforth, R. M., Lamb, J. L., Luterbacher, H., Beard, J. H. & Jeffords, R. M. (1975). Cenozoic planktonic foraminiferal zonation and characteristics of index forms. University of Kansas Paleontological Contributions, Articles. 62: 1-425. gs O

Stott, L. D. & Kennett, J. P. (1990). The Paleoceanographic and Paleoclimatic signature of the Cretaceous/Paleogene boundary in the Antarctic: Stable isotopic results from ODP Leg 113. Proceedings of the Ocean Drilling Program, Scientific Results. 113: 829-848. gs

Todd, R. (1966). Smaller Foraminifera from Guam. U.S. Geological Survey, Professional Paper. 403(1): 1-36. gs

Toumarkine, M. (1971). Etude des Foraminifères planctoniques de deux sondages (H-S49 et PGYT-31) dans l’ Eocène de la Montagne du Bakony (Transdanubie, Hongrie). Annales Instituti Geologici Publici Hungarici. 54: 283-299. gs

Toumarkine, M. (1975). Middle and Late Eocene planktonic foraminifera from the northwestern Pacific Ocean: Leg 32 of the Deep Sea Drilling Project. Initial Reports of the Deep Sea Drilling Project. 32: 735-751. gs

Toumarkine, M. (1978). Planktonic foraminiferal biostratigraphy of the Paleogene of Sites 360 to 364 and the Neogene of Sites 362A, 363 and 364 Leg 40,. Initial Reports of the Deep Sea Drilling Project. 40: 679-721. gs

Toumarkine, M. (1983). Les Foraminifères planctoniques de l’Eocène moyen et supérieur des régions tropicales à temperées chaudes. In, p1-219 (ed.) . PhD thesis, Université Pierre et Marie Curie, Paris 6 1-219. gs

van Eijden, A. J. M. & Smit, J. (1991). Eastern Indian Ocean Cretaceous and Paleogene quantitative biostratigraphy. Proceedings of the Ocean Drilling Program, Scientific Results. 121: 77-123. gs

Wade, B. S., Pearson, P. N., Berggren, W. A. & Pälike, H. (2011). Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth-Science Reviews. 104: 111-142. gs

Wade, B. S., Aljahdali, M. H., Mufrreh, Y. A., Memesh, A. M., AlSoubhi, S. A. & Zalmout, I. S. (2021). Upper Eocene planktonic foraminifera from northern Saudi Arabia: implications for stratigraphic ranges. Journal of Micropalaeontology. 40: 145-161. gs O

test outline:	Subquadrate	chamber arrangement:	Trochospiral	edge view:	Equally biconvex	aperture:	Umbilical
sp chamber shape:	Globular	coiling axis:	Low	periphery:	N/A	aperture border:	Thick lip
umb chbr shape:	Globular	umbilicus:	Wide	periph margin shape:	Broadly rounded	accessory apertures:	Sutural
spiral sutures:	Strongly depressed	umb depth:	Deep	wall texture:	Spinose	shell porosity:	Finely Perforate: 1-2.5µm
umbilical or test sutures:	Strongly depressed	final-whorl chambers:	3-3	N.B. These characters are used for advanced search. N/A - not applicable

Globigerinatheka index

Taxonomy

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

References:

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