Turborotalia ampliapertura


Classification: pf_cenozoic -> Globanomalidae -> Turborotalia -> Turborotalia ampliapertura
Sister taxa: T. cunialensis, T. cocoaensis, T. cerroazulensis, T. pomeroli, T. frontosa, T. ampliapertura, T. increbescens, T. altispiroides, T. possagnoensis, T. sp.,

Taxonomy

Citation: Turborotalia ampliapertura Bolli 1957
Rank: Species
Basionym: Globigerina ampliapertura
Synonyms: [Pearson et al. 2018]
Taxonomic discussion:

Turborotalia ampliapertura is a useful zone fossil (Bolli, 1957). Pearson and others (2006b) included Globigerina pseudoampliapertura Blow and Banner in synonymy. The evolutionary origin of ampliapertura has been somewhat problematic, with the first appearance being given as upper Eocene Zone E15 (Blow and Banner, 1962; Pearson and others, 2006b). However the most detailed information is provided by Haggag and Luterbacher (1995) who studied the evolutionary transition between Turborotalia pomeroli and Turborotalia ampliapertura (given as pseudoampliapertura) in the middle Eocene of Egypt. In that study (which was overlooked by Pearson and others, 2006b) two subspecies of pseudo-ampliapertura were named, nukhulensis and sinaiensis. In our view the latter falls within the normal range of variation of ampliapertura. The former is somewhat intermediate between pomeroli and ampliapertura and is here included in questionable synonymy with ampliapertura. The study of Haggag and Luterbacher (1995) demonstrates that ampliapertura evolved around the base of Zone E12, that is, during the middle Eocene climate optimum. Its ancestor was evidently pomeroli, not increbescens as suggested by Blow and Banner (1962) and Pearson and others (2006b). [Pearson et al. 2018]

Blow and Banner (1962) and Blow (1969, 1979) distinguished the supposed contemporaneous homeomorph Globorotalia (Turborotalia) pseudoampliapertura on the basis of differences in wall texture. The holotypes of both taxa are illustrated here by SEM for the first time (Pl.15.2, Figs. 1-3 and Pl. 15.2, Figs. 9-11), as well as better preserved specimens of ampliapertura from the type Cipero Formation supplied by F. Ro½gl (Pl.15.2, Figs. 4-6). According to Blow and Banner (1962), pseudoampliapertura possesses a “smooth, non-granular wall” and usually achieves greater size than ampliapertura, which has a “rough, ‘granular’ and hispid wall”. We attribute these differences mainly to the variable state of preservation of the material studied by Blow and Banner to the fact that the large final chamber seen in the pseudoampliapertura holotype tends to be smoother than the rest of the test surface. The ranges of the two supposed species are identical (e.g., Premoli Silva and Boersma, 1988) and other authors have experienced difficulty in separating them (e.g., Nishi and Chaproniere, 1994). Globigerina kondoi Todd, 1970, appears to be conspecific. [Pearson et al. 2006]

Catalog entries: Globigerina ampliapertura, Globigerina kondoi, Globigerina pseudoampliapertura, Turborotalia pseudoampliapertura sinaiensis, Turborotalia pseudoampliapertura nukhulensis

Type images:

Distinguishing features: Like T. increbescens but wider, more open umbilicus, more umbilically centered aperture and more globular chamber shape.

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:

Turborotalia ampliapertura is distinguished from T. increbescens by a more umbilically centered aperture and more globular chamber shape (Pearson and others, 2006b). It is common for populations to show some intergradation between these species. Specimens on Plate 14.2 have been selected to illustrate the range of variation. Some specimens can be similar in shape to Dentoglobigerina taci Pearson and Wade but are distinguished by having less incised sutures and a different wall texture.

[Pearson et al. 2018]

Wall type: Smooth, to weakly cancellate, frequently densely pustulose; tendency to defoliate. [Pearson et al. 2018]

Test morphology: Moderately high trochospiral, compact globular test with 3½-4 chambers in final whorl. Chambers inflated, appressed and embracing, increasing moderately in size. Outline lobulate or rounded in edge view. Spiral sutures slightly curved, depressed. Aperture a high arch, sometimes asymmetrical but approaching circular in some specimens, in umbilical-extraumbilical position; may have imperforate rim. Umbilicus small. Umbilical sutures moderately curved, depressed. The coiling is somewhat irregular and there is considerable variation between specimens in the shape and size of the aperture (modified from Pearson and others, 2006b). [Pearson et al. 2018]

Size: Holotype length 0.49 mm, width 0.29 mm. [Pearson et al. 2018]

Character matrix

test outline:Lobatechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Globularcoiling axis:Moderate-highperiphery:N/Aaperture border:Thin lip
umb chbr shape:Globularumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Moderately depressedumb depth:Deepwall texture:Cancellateshell porosity:Finely Perforate: 1-2.5µm
umbilical or test sutures:Moderately depressedfinal-whorl chambers:3.0-4.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


Geographic distribution: Cosmopolitan, occurring across a broad range of latitudes. The species peaks in abundance during the Eocene-Oligocene turnover and after the extinction of other Turborotalia suggesting it is an opportunistic species (Wade and Pearson, 2008). [Pearson et al. 2018]

Isotope paleobiology: Poore and Matthews (1984) recorded consistently negative δ18O values for this species indicating a shallow water, mixed-layer habitat. Wade and Pearson (2008) found it consistently offset by about +0.5 per mil from co-occurring Pseudohastigerina micra, suggesting a near surface habitat but perhaps with a component of gametogenic calcite added at depth. [Pearson et al. 2018]

Phylogenetic relations: Evolved from Turborotalia pomeroli in the middle Eocene (Haggag and Luterbacher, 1995). It became extinct in the Oligocene without leaving any descendants, bringing to an end the stratigraphic range of the Family Globanomalinidae. [Pearson et al. 2018]

Most likely ancestor: Turborotalia pomeroli - at confidence level 4 (out of 5). Data source: Haggag and Luterbacher, 1995; Pearson et al. 2018.

Biostratigraphic distribution

Geological Range:
Notes: This form ranges from around the base of middle Eocene Zone E12 (Haggag and Luterbacher, 1995, fig. 2) to lower Oligocene Zone O2 (used as a zone marker by Bolli, 1957; calibrated to Chron C11r by Leckie and others, 1993; zone denoted O2 by Berggren and Pearson, 2005). [Pearson et al. 2018]
Last occurrence (top): at top of O2 zone (100% up, 30.3Ma, in Rupelian stage). Data source: zonal marker (Wade et al. 2011)
First occurrence (base): in mid part of E15 zone (50% up, 35.3Ma, in Priabonian stage). Data source: Pearson et al. (2006), fig. 15.1

Plot of occurrence data:

Primary source for this page: Pearson et al. 2018 - Olig Atlas chap.14 p.408; Pearson et al. 2006 - Eocene Atlas, chap. 15, p. 441

References:

Berggren, W. A. & Pearson, P. N. (2005). A revised tropical to subtropical Paleogene planktonic foraminiferal zonation. Journal of Foraminiferal Research. -. 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

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. (1957b). Planktonic foraminifera from the Oligocene-Miocene Cipero and Lengua formations of Trinidad, B.W.I. 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: 97-123. gs

Haggag, M. A. & Luterbacher, H. (1995). The Turborotalia pseudoampliapertura lineage in the Eocene of the Wadi Nukhul section, Sinai, Egypt. Revue de Micropaléontologie. 38: 37-47. gs

Jenkins, D. G. (1965b). Planktonic Foraminiferal zones and new taxa from the Danian to lower Miocene of New Zealand. New Zealand Journal of Geology and Geophysics. 8(6): 1088-1126. gs

Leckie, R. M., Farnham, C. & Schmidt, M. G. (1993). Oligocene planktonic foraminifer biostratigraphy of Hole 803D (Ontong Java Plateau) and Hole 628A (Little Bahama Bank), and comparison with the southern high latitudes. Proceedings of the Ocean Drilling Program, Scientific Results. 130: 113-136. gs

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

Pearson, P. N. & Wade, B. S. (2015). Systematic taxonomy of exceptionally well-preserved planktonic foraminifera from the Eocene/Oligocene boundary of Tanzania. Cushman Foundation for Foraminiferal Research, Special Publication. 45: 1-85. gs

Pearson, P. N., Premec-Fucek, V. & Premoli Silva, I. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Turborotalia. 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 15): 433-460. gs

Pearson, P. N., Olsson, R. K., Spezzaferri, S. & Leckie, R. M. (2018a). Taxonomy, biostratigraphy, and phylogeny of Oligocene Globanomalinidae (Turborotalia and Pseudohastigerina). In, Wade, B. S. , Olsson, R. K. , Pearson, P. N. , Huber, B. T. & Berggren, W. A. (eds) Atlas of Oligocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication. 46(Chap 14): 403-414. gs

Poore, R. Z. & Brabb, E. E. (1977). Eocene and Oligocene planktonic foraminifera from the Upper Butano sandstone and type San Lorenzo formation, Santa Cruz Mountains, California. Journal of Foraminiferal Research. 7(4): 249-272. gs

Poore, R. Z. & Bybell, L. M. (1988). Eocene to Miocene biostratigraphy of New Jersey Core ACGS #4: Implications for regional stratigraphy. U.S. Geological Survey Bulletin. 1829: 1-41. gs

Poore, R. Z. & Matthews, R. K. (1984). Oxygen isotope ranking of late Eocene and Oligocene planktonic foraminifers: implications for Oligocene sea-surface temperatures and global ice-volume. Marine Micropaleontology. 9: 111-134. gs

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

Premoli Silva, I. & Boersma, A. (1988). Atlantic Eocene planktonic foraminiferal historical biogeography and paleohydrographic indices. Palaeogeography, Palaeoclimatology, Palaeoecology. 67: 315-356. gs

Pujol, C. (1983). Cenozoic planktonic foraminiferal biostratigraphy of the South-Western Atlantic (Rio Grande Rise): Deep Sea Drilling Project Leg 72. Initial Reports of the Deep Sea Drilling Project. 72: 623-673. gs

Todd, R. (1970b). Smaller foraminifera of late Eocene age from Eua, Tonga. U. S. Geological Survey, Professional Paper. 640-A: 1-23. gs

Wade, B. S. & Pearson, P. N. (2008). Planktonic foraminiferal turnover, diversity fluctuations and geochemical signals across the Eocene/Oligocene boundary in Tanzania. Marine Micropaleontology. 68: 244-255. gs


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Turborotalia ampliapertura compiled by the pforams@mikrotax project team viewed: 22-11-2019

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