Dentoglobigerina


Classification: pf_cenozoic -> Globigerinidae -> Dentoglobigerina
Sister taxa: Beella, Globigerina, Globigerinella, Protentella, Quiltyella, Ciperoella, Globigerinoides, Globigerinoidesella, Globoturborotalita, Orbulina, Praeorbulina, Sphaeroidinella, Sphaeroidinellopsis, Trilobatus, Turborotalita, Dentoglobigerina, Globoquadrina, Catapsydrax, Clavatorella, Paragloborotalia, Protentelloides, Eoglobigerina, Globigerinatheka, Globorotaloides, Guembelitrioides, Orbulinoides, Parasubbotina, Pseudoglobigerinella, Subbotina,
Daughter taxa: (blue => in age window 0-300Ma)
tapuriensis -> binaiensis lineage
Like D. binaiensis but with 4 rather than 3 chambers in the final whorl, less rapid chamber expansion and a more open umbilicus.
Like D. sellii but with larger final chamber and acutely cut-off apertural face as seen in side view; with reduced porosity or smooth areas on the apertural face, and with thickened rims on the chamber shoulders.
Like D. tapuriensis, but with more rapidly expanding chambers, a more flattened umbilical face to the final chamber, and a more spherical overall morphology.
3 compressed chambers in final whorl.
Umbilicus elliptical, deep; with thin lip.
galavisi -> baroemensis lineage
Like D. larmeui but chambers more angular, disjunct and slightly reniform; outline more trapezoidal outline; umbilicus broad & deep.
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).
3 moderately compressed chambers in final whorl.
Umbilicus broadly triangular; with asymmetrical narrow tooth.
globular -> altispira lineage
High trochospiral. Aperture umbilical with teeth projecting into umbilicus
Like D. globularis but with 5-6 chambers in the final whorl leading to a more lobulate outline; also wider umbilicus.
Like D. galavisi but larger, more open coiling with 3½-4 chambers in the whorl (vs. 3-3½), more open umbilicus, less embracing chambers, and slightly higher spire.
Other species
3½ globular slightly compressed chambers in final whorl.
Umbilicus rectangular, broad, open; with thin lip. No spine holes
3-3½ globular slightly compressed chambers in final whorl.
Umbilicus narrow triangular, with irregular pustulose tooth.
3½ globular chambers in final whorl.
Umbilicus open, square; with thin lip.
Test compact, subcircular to subquadrate; cap-like final chamber extends over umbilicus.
Aperture umbilically centered; with an irregular, subtriangular lip.

Like D. tripartita but smaller, and less spherical, less compressed/reniform overall morphology.


Large to very large, robust, outline circular; 3½-4 embracing, reniform chambers in the final whorl, final chamber commonly reduced in size and flattened; umbilicus small, commonly triangular may have a tooth 


Specimens which cannot be assigned to established species

Taxonomy

Citation: Dentoglobigerina Blow, 1979
Rank: Genus
Type species: Globigerina galavisi Bermúdez, 1961
Taxonomic discussion:

As discussed under Family Globigerinidae above, the Working Group now regards Dentoglobigerina as having been spinose in life, at least in its primitive condition. Fox and Wade (2013) illustrated spine holes in the Miocene species D. juxtabinaiensis and Pearson and Wade (2015) illustrated spine holes or possible spine holes in D. galavisi, D. pseudovenezuelana, D. taci, D. tapuriensis, and D. cf. tripartita (= D. eotripartita n. sp. in this work). Here we present additional evidence for spine holes in D. baroemoenensis, D. larmeui, and D. binaiensis. Species for which spine holes have not yet been observed are: D. globosa, D. globularis, D. prasaepis, D. sellii, D. tripartita, D. venezuelana and Globoquadrina dehiscens. It seems that some species in the genus may have been quite densely spinose in life while others were sparsely spinose or even secondarily nonspinose (i.e., lost spines during their evolution). [Wade et al 2018]

Whereas Olsson and others (2006) suggested that Dentoglobigerina was derived from the muricate Eocene genus Acarinina, we now think an origin in the spinose genus Subbotina is much more likely (see discussion under Family Globigerinidae above), as suggested previously for example by Blow (1979) and Bolli and Saunders (1985) (see also Pearson and Wade, 2015). The ancestral form could have been Subbotina yeguaensis, which frequently has an umbilical tooth, and could have given rise to D. galavisi in the middle Eocene (Zone E12). [Wade et al 2018]

According to Blow’s (1979) original definition, the genus requires a globigeriniform morphology and the presence of an umbilical tooth, hence the name Dentoglobigerina. However, observations of modern species e.g., Dentoglobigerina cf. conglomerata and the unrelated Neogloboquadrina dutertrei show that a tooth can vary greatly between individuals and is not always present. As discussed by Pearson and Wade (2015), Blow’s definition would unite a variety of unrelated species and exclude some potentially closely related forms. Some Dentoglobigerina species (e.g., galavisi) consistently have a very prominent umbilical tooth, while in other species the tooth is generally absent (e.g., tapuriensis). Here we emphasize that the umbilical tooth is a variable character and should not be part of the generic diagnosis although it can help in identifying species. We follow Pearson and Wade (2015) by allowing forms without a tooth within the genus Dentoglobigerina but restricting it to D. galavisi and its likely descendants. We exclude various toothed forms with inflated, spherical chambers, which are better placed in Subbotina (see Chapter 10, this volume). [Wade et al 2018]

Several species of Dentoglobigerina are distinctly pustulose, particularly on the umbilical face, with a concentration of pustules in the umbilical region and on the umbilical shoulders. The pustules can be large and abundant, particularly in the species D. sellii. [Wade et al 2018]

The genus Dentoglobigerina, as used here in the phylogenetic sense, includes the D. galavisi - D. globularis - D. altispira globulosa - D. altispira altispira lineage (Text Fig. 20). It includes morphotypes with umbilical teeth over an umbilically restricted aperture. Dentoglobigerina is morphologically intermediate between Globigerina and Globoquadrina. It resembles Globigerina by exhibiting an umbilically restricted aperture and Globoquadrina in possessing one or more umbilical teeth. The genus evolved in the late Oligocene and is largely confined to the Miocene. [Kennett & Srinivasan 1983]

Catalog entries: Dentoglobigerina;

Type images:

Distinguishing features: Trochospiral test with umbilically restricted aperture and usually one or more umbilical teeth

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 is distinguished from Globoquadrina by the more globular morphology, and by lacking the highly compressed chambers and quadrate test shape of that genus. Dentoglobigerina is distinguished from Subbotina by its less lobulate equatorial outline, more compressed chambers and commonly pustulose umbilical shoulders. According to Pearson and Wade (2015:17) “the chief difference is that the chambers [in Dentoglobigerina] are generally more compressed and more closely appressed than in Subbotina, with the test as a whole more tightly coiled. Characteristically, in edge view, the final chamber frequently appears flattened and leans over the umbilicus. There is also a much greater tendency toward pustulose wall texture, especially in the umbilical region”. The aperture in Dentoglobigerina is almost always (but not exclusively) umbilical, whereas many Subbotina species have an intra-extraumbilical aperture. In addition, the sutures in Dentoglobigerina are generally more weakly defined than in Subbotina. [Wade et al 2018]

Wall type: Cancellate, normal perforate, probably spinose or sparsely spinose in life, commonly pustulose in umbilical region. [Wade et al 2018]

Test morphology: Trochospiral, globular, rounded to lobulate in outline, final chamber leaning towards the umbilicus with an ill-defined apertural face in most species; weakly to coarsely pustulose with a concentration of pustules commonly seen around the umbilicus. Primary aperture umbilical, narrow to wide, commonly hidden in umbilical view, often with pustulose apertural lip or an asymmetrical triangular tooth, but in some species no tooth occurs, a bulla may be present, and is more common in late Oligocene and early Miocene forms. [Wade et al 2018]

Biogeography and Palaeobiology


Geographic distribution: Global in mid- to low latitudes. [Wade et al 2018]

Phylogenetic relations: The genus was probably derived from Subbotina in the middle Eocene, possibly S. yeguaensis, which shows closest morphological similarity to D. galavisi. The genus gave rise to Globoquadrina in the early Miocene. [Wade et al 2018]

Most likely ancestor: Subbotina - at confidence level 2 (out of 5). Data source: Wade et al 2018.

Biostratigraphic distribution

Geological Range:
Notes: Middle Eocene (Zone E12) to Recent. [Wade et al 2018]
Last occurrence (top): in mid part of Piacenzian Stage (47% up, 3.1Ma, in Piacenzian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Lutetian Stage (69% up, 43.2Ma, in Lutetian stage). Data source: Total of range of species in this database

Plot of occurrence data:

Primary source for this page: Wade et al. 2018 - Olig Atlas chap.11 p.334 (major revision of Olsson et al. 2006, chapter 13, p. 401); Kennett & Srinivasan 1983, p.188

References:

Bermudez, P.J., (1961). Contribucion al estudio de las Globigerinidea de la region Caribe-Antillana (Paleoceno-Reciente). Mem. III Congreso Geol. Venez., 3. Editorial Sucre, Caracas, 1119-1393 pp.

Blow, W.H., (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea), 2. E. J. Brill, Leiden, 1413 pp.

Fox, L.R. & Wade, B.S., (2013). Systematic taxonomy of early–middle Miocene planktonic foraminifera from the equatorial Pacific Ocean: Integrated Ocean Drilling Program, Site U1338. Journal of Foraminiferal Research, 43: 374-405.

Hemleben, C.; Mhlen, D.; Olsson, R.K. & Berggren, W.A., (1991). Surface texture and the first occurrence of spines in planktonic foraminfera from the early Tertiary. Geologisch Jarhbuch, 128: 117-146.

Kennett, J.P. & Srinivasan, M.S., (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania, 1-265 pp.

Olsson, R.K.; Hemleben, C. & Pearson, P.N., (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene Dentoglobigerina. In: Pearson, P.N. et al. (Editors), Atlas of Eocene Planktonic Foraminifera. Cushman Foundation Special Publication. 41 Allen Press, Lawrence, Kansas, pp. 401-412.

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

Wade, B.S.; Pearson, P.N.; Olsson, R.K.; Fraass, A.J.; Leckie, R.M. & Hemleben, C., (2018). Taxonomy, biostratigraphy, and phylogeny of Oligocene and Lower Miocene Dentoglobigerina and Globoquadrina. In: Wade, B.S. et al. (Editors), Atlas of Oligocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research Special Pulbication. 46, pp. 331-385.


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Dentoglobigerina compiled by the pforams@mikrotax project team viewed: 18-10-2018

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