Globigerinella molinae Like G. navazuelensis but slightly more radially elongated last and/or penultimate chambers and single equatorial aperture.
Globigerinella navazuelensis Aperture symmetrical, sometimes double arch, with a thick rim. Planispiral coiling in the last whorl; chambers globular, not elongated.
Globigerinella obesa Low trochospiral lobulate test, 4 chambers in the last whorl, extraumbilical to equatorial aperture; bulloides-type wall texture.
Globigerinella sp. Specimens which cannot be assigned to established species
Taxonomy
Citation: Globigerinella Cushman 1927taxonomic rank: genusType species: Globigerina aequilateralis Brady, 1879 - a synonym of G. siphoniferaVariants:
Hastigerina (Bolliella) Banner & Blow 1959 = Bolliella Banner & Blow 1959 - species with elongoate chambers and apertural lip. "Even though a number of workers believe that Bolliella should be considered a junior synonym of Globigerinella, I believe the chamber elongation and the presence of an apertural lip in Bolliella to be sufficient and easily recognisable morphologic characters for distinguishing Bolliella from Globigerinella. In addition I believe that the adamsi, calida, praecalida and praeadamsi morphotypes share enough characteristics for them all to be referred to Bolliella" [Chaproniere 1991]
Taxonomic discussion: Cushman erected the genus Globigerinella for the forms with an initial trochoid test that later becomes nearly planispiral in the adult, globular to ovate chambers, umbilical aperture, and fine spines covering the test. Bolli et al. (1957) considered Globigerinella as junior synonym of Hastigerina Thomson. Bé (1969) discussed the surface ultrastructures (particularly the nature of spines) of Globigerinella and Hastigerina and concluded that these two genera are inseparable but later (Tolderlund and Bé, 1971) considered them as separate taxa. This latter view is followed here (compare also Parker, 1967; Saito et al., 1976, 1981). Globigerinella differs from Hastigerina in possessing simple rounded spines (in cross-section), which become triradiate only in later growth, as compared to the consistently triradiate spines of Hastigerina. The early members of Globigerinella (Ge. obesa, Ge. pseudobesa) resemble Jenkinsella in general test morphology but are distinguished primarily by their spinose surface ultrastructure. [Kennett & Srinivasan 1983]
Globigerinella is a common genus in the Neogene and is present in modern oceans. Globigerinella was considered by Bolli (1957) as a junior synonym of Hastigerina Thomson due to the common planispiral form. The advent of wall texture based classifications resulted in clear distinctions between these genera based on spine morphology and shell ultrastructure; see discussion in Kennett and Srinivasan (1983). DNA-based studies have revealed high genetic diversity in G. siphonifera with different genotypes having been detected with corresponding morphologies (Bijma and others, 1998; de Vargas and others, 2002). They show subtle differences in ecology and physiology, their empty shells are difficult to differentiate, although some small morphological differences are recognized, and should thus be best regarded as sister species (Huber and others, 1997; Bijma and others, 1998; de Vargas and others, 2002). We cannot exclude that also the fossil Globigerinella possessed multiple genotypes, but lacking DNA studies it cannot be demonstrated. The genus first appears in the lower Oligocene. A series of Oligocene globigerinellids described from the Paratethys region, Indian Ocean and Pacific, developed radially elongate chambers in the final whorl. Among these are several species previously attributed to the genus Protentella. We have reviewed the taxonomy of these digitate forms and explored possible evolutionary connections. We recognize however, that it is very possible that some or all of these forms represent independent derivations of similar clavate/digitate forms from a globigerinellid ancestor close to G. obesa or G. praesiphonifera. [Spezzaferri et al. 2018]
Distinguishing features: Parent taxon (Globigerinidae): Wall spinose, usually with 3½-6 globular chambers in final whorl, trochospiral or planispiral This taxon: Test initially trochospiral, becoming nearly planispiral; globular to ovate chambers; aperture umbilical; fine spines cover the test
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
Morphology: Test trochospiral in initial stages becoming planispiral in adult stage, with 4 to several globular to ovate chambers, moderately inflating in the ultimate whorl. Aperture umbilical-extraumbilical, interiomarginal, sometimes divided in two by a median septum. A spiral sutural opening of the ultimate chamber may be present. [Spezzaferri et al. 2018] Wall type: Spinose; spines are supported by spine collars which coalesce to form ridges. Pore concentrations range from around 75 to 100 pores/50 μm2 test surface area and pore diameters range from around 1.6 μm to 3.5 μm. [Spezzaferri et al. 2018]
Biogeography and Palaeobiology
Geographic distribution Isotope paleobiologyModern Globigerinella siphonifera are symbiont bearing, and inhabit the mixed-layer of oligotrophic, tropical to subtropical water masses. The isotopic composition of Type I and Type II of G. siphonifera are strongly influenced by feeding regime and light intensity rather than depth habitat (Bijma and others, 1998). [Spezzaferri et al. 2018] Phylogenetic relationsGlobigerinella probably originated from Globigerina archaeobulloides in the lower Oligocene. [Spezzaferri et al. 2018]
Geological Range: Notes: Lower Oligocene Zone O1 (Spezzaferri, 1994) to Recent (e.g., Hemleben and others, 1989) [Spezzaferri et al. 2018] Last occurrence (top): Extant. Data source: Total of ranges of the species in this database First occurrence (base): within O1 zone (32.10-33.90Ma, base in Priabonian stage). Data source: Total of ranges of species in this database
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
Neptune data: This is a higher taxon page so Neptune data is not plotted. See also: customisable plot Parent: Globigerinidae
Primary source for this page: Spezzaferri et al. 2018 - Olig Atlas chap.6 p.188; Kennett & Srinivasan 1983, p.234
References:
Banner, F. T. & Blow, W. H. (1959). The classification and stratigraphical distribution of the Globigerinaceae. Palaeontology. 2(1): 1-27. gs
Bijma, J., Hemleben, C., Huber, B. T., Erlenkeuser, H. & Kroon, D. (1998). Experimental determination of the ontogenetic stable isotope variability in two morphotypes of Globigerinella siphonifera (d’Orbigny). Marine Micropaleontology. 35: 141-160. 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
Brady, H. B. (1879). Notes on some of the reticularian Rhizopoda of the "Challenger" expedition. I.- On new or little known arenaceous types. Quarterly Journal of Microscopical Science. 19: 20-63. gs
Chaproniere, G. C. H. (1991). Pleistocene to Holocene planktic foraminiferal biostratigraphy of the Coral Sea, offshore Queensland, Australia. BMR Journal of Australian Geology and Geophysics. 12: 195-221. gs
Cushman, J. A. (1927a). An outline of a re-classification of the Foraminifera. Contributions from the Cushman Laboratory for Foraminiferal Research. 3: 1-105. gsO
Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs
Spezzaferri, S., Coxall, H. K., Olsson, R. K. & Hemleben, C. (2018a). Taxonomy, biostratigraphy, and phylogeny of Oligocene Globigerina, Globigerinella, and Quiltyella n. gen. 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 6): 179-214. gs
Globigerinella compiled by the pforams@mikrotax project teamviewed: 16-10-2024
