Dentoglobigerina larmeui


Classification: pf_cenozoic -> Globigerinidae -> Dentoglobigerina -> Dentoglobigerina larmeui
Sister taxa: D. juxtabinaiensis, D. binaiensis, D. sellii, D. tapuriensis, D. baroemoenensis, D. larmeui, D. galavisi, D. altispira, D. globosa, D. globularis, D. prasaepis, D. pseudovenezuelana, D. taci, D. tripartita, D. eotripartita, D. venezuelana, D. sp.,

Taxonomy

Citation: Dentoglobigerina larmeui (Akers, 1955)
Rank: species
Basionym: Globoquadrina larmeui Akers, 1955
Synonyms:
Taxonomic discussion:

We illustrate the holotype of larmeui in SEM for the first time. This shows that Akers’s type illustration in spiral view is slightly misleading as drawn from an oblique angle, giving the outline a more asymmetrical, lobulate appearance than is seen in our more orthodox orientation. Dentoglobigerina larmeui is a rather generalized morphologic species that in our taxonomy forms a link between D. galavisi (typical of the upper Eocene and Oligocene) and both D. baroemoenensis and Globoquadrina dehiscens (forms that are typical of the lower to middle Miocene). Its close similarity to galavisi was already noted by Bermúdez (1961) and Brönnimann and Resig (1971), and the distinction between these forms can be very subjective, particularly among variable populations, making the highest occurrence of galavisi and lowest occurrence of larmeui difficult to locate precisely. Jenkins (1960) illustrated two specimens as larmeui from the Oligocene and Miocene of the Lakes Entrance Oil Shaft in Victoria, Australia which nicely illustrate the difference between the morphologies, the older one (pl. 3, fig. 1a-c) being assigned to galavisi in this study. Transitional stages in the evolution of D. larmeui from D. galavisi are the development of a broader umbilicus, more flattened apertural face, and a more symmetrical triangular umbilical tooth. These trends become more fully enhanced in the evolution of Globoquadrina dehiscens. Iaccarino (1985) noted its similarity to Globoquadrina langhiana Cita and Gelati from the type Langhian (middle Miocene) of Italy, although we have not investigated this possible synonymy. We illustrate specimens that show evidence of a true spine and spine collar (Plate 11.8, Figs. 7 and 8). [Wade et al. 2018]

Catalog entries: Globoquadrina larmeui

Type images:

Distinguishing features: Like D. galavisi but slightly wider and more open umbilicus and more distinctly flattened umbilical face to the final chamber, giving rise to a somewhat quadrate form; also typically 3½-4 chambers in the final whorl (vs. 3-3½).

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:

Dentoglobigerina larmeui (the holotype of which is from the middle Miocene) closely resembles D. galavisi (holotype from the upper Eocene) but is distinguished by the slightly wider and more open umbilicus and more distinctly flattened umbilical face to the final chamber, giving rise to a somewhat quadrate form. Dentoglobigerina larmeui typically has 3½-4 chambers in the final whorl, compared to 3-3½ in galavisi, which tends to produce a more square and symmetrical umbilicus in larmeui as opposed to a more triangular, asymmetrical umbilicus that is typical of galavisi. The umbilical tooth is usually less well developed in D. larmeui, and there is more of a tendency to form a reduced bulla. Dentoglobigerina larmeui differs from D. globularis by the the more compact and flattened nature of the final whorl chambers. Dentoglobigerina larmeui differs from D. baroemoenensis by having more embracing chambers, less reniform, more subspherical chambers, and a narrower umbilicus. This species differs from Globoquadrina dehiscens by lacking the ‘boxy’ outline, strongly embracing chambers, and flat, imperforate apertural face of this Miocene taxon. Transitional specimens between to G. dehiscens are shown on Plate 11.8. [Wade et al. 2018]


Wall type: Normal perforate, cancellate, probably spinose in life.

Test morphology: Low trochospiral, globular, to subquadrate, slightly lobulate; in spiral view 3½-4 flattened, ovoid-shaped chambers in final whorl increasing rapidly in size, sutures straight, moderately depressed; in umbilical view 3½-4 subspherical chambers in final whorl increasing rapidly in size, final chamber distinctly flattened and sloped toward the umbilicus, may have a reduced bulla-like final chamber which extends over the umbilicus; umbilicus open, broad, aperture umbilical, bordered by a small triangular lip, sutures straight or slightly curved, weakly depressed; in edge view very low trochospiral, oval, rounded in outline, with final chamber extending over the umbilicus. [Wade et al. 2018]

Size: Maximum diameter of holotype 0.35 mm, minimum diameter 0.28 mm, thickness 0.24 mm. [Wade et al. 2018]

Character matrix

test outline:Subquadratechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical
sp chamber shape:Globularcoiling axis:Moderateperiphery:N/Aaperture border:Thin flange
umb chbr shape:Globularumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Moderately depressedumb depth:Deepwall texture:Cancellateshell porosity:Finely Perforate: 1-2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:0.0-0.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


Geographic distribution: Cosmopolitan; recorded at 63oN at DSDP Site 407 (Poore, 1979). [Wade et al. 2018]

Isotope paleobiology: This species had an upper thermocline habitat according to Pearson and Wade (2009). [Wade et al. 2018]

Phylogenetic relations: This species evolved from Dentoglobigerina galavisi and gave rise to both Globoquadrina dehiscens and Dentoglobigerina baroemoenensis. [Wade et al. 2018]

Most likely ancestor: Dentoglobigerina galavisi - at confidence level 3 (out of 5). Data source: Wade et al. 2018.
Likely descendants: Dentoglobigerina baroemoenensis; Globoquadrina dehiscens;

Biostratigraphic distribution

Geological Range:
Notes: The oldest illustrated specimen that we assign to this species is from Spezzaferri and Premoli Silva (1991), from Subzone P21a of DSDP Hole 538A, from a sample overlapping the range of Ciperoella angulisuturalis in that hole (= Zone O4). It has been recorded as low as Zone P19 (= Zone O1) in Spezzaferri and Premoli Silva (1991), but we have not been able to confirm this. It extends until at least the type level in the middle Miocene, and we have not investigated its highest occurrence, or its possible relationship with Globoquadrina larmeui obesa Akers from the Pliocene. [Wade et al. 2018]
Last occurrence (top): within M1a subzone (22.44-22.96Ma, top in Aquitanian stage). Data source:
First occurrence (base): within O2 zone (30.28-32.10Ma, base in Rupelian stage). Data source:

Plot of occurrence data:

Primary source for this page: Wade et al. 2018 - Olig Atlas chap.11 p.353

References:

Akers, W. H. (1955). Some planktonic foraminifera of the American Gulf Coast and suggested correlations with the Caribbean Tertiary. Journal of Paleontology. 29(4): 647-664. gs

Berggren, W. A., Aubry, M. -P. & Hamilton, N. (1983). Neogene magnetobiostratigraphy of DSDP Site 516, Rio Grande Rise (South Atlantic). Initial Reports of the Deep Sea Drilling Project. 72: 675-713. gs

Bermudez, P. J. (1961). Contribucion al estudio de las Globigerinidea de la region Caribe-Antillana (Paleoceno-Reciente). Editorial Sucre, Caracas. 1119-1393. gs

Blow, W. H. (1959). Age, correlation, and biostratigraphy of the upper Tocuyo (San Lorenzo) and Pozon Formations, eastern Falcon, Venezuela. Bulletins of American Paleontology. 39(178): 67-251. 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

Chaisson, W. P. & Leckie, R. M. (1993). High-resolution Neogene planktonic foraminifer biostratigraphy of Site 806, Ontong Java Plateau (Western Equatorial Pacific). Proceedings of the Ocean Drilling Program, Scientific Results. 130: 137-178. gs

Iaccarino, S. (1985). Mediterranean Miocene and Pliocene planktic foraminifea. In, Bolli, H. M. , Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambrige University Press, Cambrige 283-314. gs

Jenkins, D. G. (1960). Planktonic foraminifera from the Lakes Entrance oil shaft, Victoria, Australia. Micropaleontology. 6: 345-371. gs

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

LeRoy, L. W. (1939). Some small foraminifera ostracoda and otoliths from the Neogene (Miocene) of the Rokan-Tapanoeli area, central Sumatra,. Natuurk. Tijdschr. Nederl.-Indie.. 99(6): 215-296. gs

Pearson, P. N. & Wade, B. S. (2009). Taxonomy and stable isotope paleoecology of well-preserved planktonic foraminifera from the uppermost Oligocene of Trinidad. Journal of Foraminiferal Research. 39: 191-217. gs

Poore, R. Z. (1979). Oligocene through quarternary planktonic foraminiferal biostratigraphy of the North Atlantic: DSDP LEG 49. Initial Reports of the Deep Sea Drilling Project. 49: 447-517. gs

Quilty, P. G. (1976). Planktonic foraminifera DSDP Leg 34, Nazca Plate. Initial Reports of the Deep Sea Drilling Project. 34: 629-703. gs

Spezzaferri, S. & Premoli Silva, I. (1991). Oligocene planktonic foraminiferal biostratigraphy and paleoclimatic interpretation from Hole 538A, DSDP Leg 77, Gulf of Mexico. Palaeogeography, Palaeoclimatology, Palaeoecology. 83: 217-263. gs

Spezzaferri, S. (1994). Planktonic foraminiferal biostratigraphy and taxonomy of the Oligocene and lower Miocene in the oceanic record. An overview. Palaeontographia Italica. 81: 1-187. gs

Wade, B. S., Pearson, P. N., Olsson, R. K., Fraass, A. J., Leckie, R. M. & Hemleben, C. (2018c). Taxonomy, biostratigraphy, and phylogeny of Oligocene and Lower Miocene Dentoglobigerina and Globoquadrina. 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 11): 331-384. gs


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Dentoglobigerina larmeui compiled by the pforams@mikrotax project team viewed: 6-12-2019

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