Globigerinina

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Globigerinina
Temporal range: Toarcian–Recent
Globigerina.svg
Scientific classification Red Pencil Icon.png
Clade: SAR
Phylum: Foraminifera
Class: Globothalamea
Order: Rotaliida
Suborder: Globigerinina
Delage & Hérouard, 1896
Superfamilies

The Globigerinina is a suborder of foraminiferans that are found as marine plankton. They produce hyaline calcareous tests, and are known as fossils from the Jurassic period onwards. The group has included more than 100 genera and over 400 species, of which about 30 species are extant. One of the most important genera is Globigerina ; vast areas of the ocean floor are covered with Globigerina ooze (named by Murray and Renard in 1873), dominated by the shells of planktonic forms.

Contents

Description

Globigerinids are characterized by distinctly perforate planispiral or trochospiral tests composed of lamellar radial hyaline (glassy) calcite, with typically globular chambers and single interiomarginal aperture. Some however have multiple or auxiliary apertures, and in some the aperture is areal or terminal in location. Some, also, have keels, reinforcing thickenings along exterior angles. An adaptation to the planktonic habit is the development of long narrow spines that support a frothy buoyant ectoplasm.

Superfamilies and families

The Globigerinina are now divided into these superfamilies and families: [1]

Related Research Articles

<i>Globigerina</i> Genus of single-celled organisms

Globigerina is a genus of planktonic Foraminifera, in the order of Rotaliida. It has populated the world's oceans since the Middle Jurassic.

Fusulinida Extinct order of single-celled organisms

The Fusulinida is an extinct order within the Foraminifera in which the tests are composed of secreted hyaline calcite. Like all forams, they were single-celled organisms. In advanced forms the test wall was differentiated into two or more layers. Loeblich and Tappan, 1988, gives a range from the Lower Silurian to the Upper Permian, with the fusulinid foraminifera going extinct with the Permian–Triassic extinction event. While the latter is true, a more supported projected timespan is from the Mid-Carboniferous period.

Rotaliida Order of single-celled organisms

The Rotaliida are an order of Foraminifera, characterized by multilocular tests (shells) composed of bilamellar perforate hyaline lamellar calcite that may be optically radial or granular.

Abadehella is a genus of large Upper Permian benthic forams in the order Fusulinida. Their outer test is conical, up to 1.35mm at the concave base, coiled trochospirally with up to twenty whorls, each with one and a half to two low chambers surrounding the open umbilicus. Chambers are subdivided by close, evenly spaced radial beams. The test wall is calcareous and two-layered, with an external wall with an outer dark microgranular layer and an inner light fibrous layer, septa and beams with a single micro-granular layer. The aperture from each chamber opens into the umbilical region beneath a short projection.

Abathomphalus is a genus of foraminifera included in the Globotruncanid family.

Hantkeninoidea is a superfamily of foraminifera with planispiral or enrolled biserial tests, found in marine sediments of Paleocene to Miocene age, in which chambers vary from globular to elongate and the primary aperture is equatorial in position. It contains one family, the Hantkeninidae.

Acervulinacea is a superfamily in the Foraminifera order Rotaliida. The Acervulinacea may be free, or able to move about, or their tests may be attached to some substrate. The early growth stage is spiral, followed by irregular chambers that form an irregular mass, disc, or branching structure. The test wall is of hyaline (glassy) optically radial calcite and is coarsely perforate. Apertures are present only as mural pores.

Globigerinoidea Superfamily of foraminifers

Globigerinoidea is a superfamily of free-living, calcareous, planktonic foraminiferal protists that have lived in the open ocean since the Eocene. It is part of the suborder Globigerinina.

Miliamellus is a genus of Cenozoic benthic foraminifera with tests made of imperforate opaline silica. It is the only genus in the order Silicoloculinida and the family Silicoloculinidae. It is sometimes referred to by the junior synonym Silicoloculina.

<i>Cibicides</i> Genus of foraminifers

Cibicides is a genus of cosmopolitan benthic foraminifera known from at least as far back as the Paleocene that extends down to the present.

<i>Cassidulina</i> (foraminifera) Genus of foraminifers

Cassidulina is a genus of foraminifera described in the Treatise Part C., as having a free, lenticular test, with central boss of clear calcite on either side. Chambers are biserially arranged, enrolled planispirally with a subangular to keeled periphery. The wall is calcareous, hyaline (glassy), optically granular, perforate. The surface is smooth with a polished appearance. Sutures are radial to oblique, straight or curved. The aperture is a narrow arched slip at the base of the apertural face, partly closed by an apertural place.

The Planorbulinacea are a superfamily of rotalliid foraminifera that has been extant since the Early Cretaceous (Berriasian), characterized by trochospiral tests, at least in early stage but which later may become uncoiled. The test wall is of perforate hyaline calcite, commonly optically radial in structure, with crystallographic c-axes perpendicular to the surface. The apertural face may be imperforate; the aperture interiomarginal and extraumbilical-umbilical to nearly equatorial in coiled forms, subterminal in uncoiled forms.

Hedbergella is an extinct genus of planktonic foraminifera from the Cretaceous, described by Loeblich and Tappan, 1961, as:

Test free, trochospiral, biconvex, umbilicate, periphery rounded with no indication of keel or poreless margin; chambers globular to ovate; sutures depressed, radial, straight or curved; wall calcareous, finely perforate, radial in structure, surface smooth to hispid or rugose; aperture an interiomarginal, extraumbilical-umbilical arch commonly bordered above by a narrow lip or spatulate flap, ... Includes species otherwise similar to Praeglobotruncana but which lack a keel or poreless margin, hence is regarded as a separate genus rather than as a subgenus of Praeglobotruncana as by Banner and Blow (1959).

A protist is any eukaryotic organism that is not an animal, plant, or fungus. The protists do not form a natural group, or clade, since they exclude certain eukaryotes with whom they share a common ancestor; but, like algae or invertebrates, the grouping is used for convenience. In some systems of biological classification, such as the popular five-kingdom scheme proposed by Robert Whittaker in 1969, the protists make up a kingdom called Protista, composed of "organisms which are unicellular or unicellular-colonial and which form no tissues".

The Globoroatioidea constitutes a superfamily of Cenozoic plantonic foraminifera. It is part of the suborder Globigerinina. Globoroatioidea have trochospiral tests with rounded to carinate peripheries, the walls of which are of finely lamellar, perforate, of optically radial calcite, with an inner organic lining. The surface of these tests is smooth, lacking spines, but may be covered with pustules or pitted, and may have one or more large pores at the center. There is a single primary aperture that may be bordered by an imperforate lip, as well as possible supplementary apertures.

Gansserina is a genus of planktonic foraminifera, included in the globigerinid family Globotruncanidae, that had a fairly wide distribution in the Late Cretaceous (Maastrichtian). The type species is Gansserina gansseri.

Rotaliana is a subclass of benthic Foraminifera with multichambered tests of perforate hyaline calcite. Tests may be planospiral, low or high trochospiral, or serial. Interiors may be complex with secondary chambers and interconnecting canal systems. Rotaliana are separate from the planktonic Globigerinana although both have tests of similar composition. The Textulariana, which contains forms that are rather similar, differs in be agglutinated.

Truncorotaloididae is a family of foraminifera belonging to the superfamily Globorotalioidea in the suborder Globigerinina and the order Rotaliida. It is found in marine sediments from the middle Paleocene to the upper Eocene.

Chilostomelloidea is a superfamily of foraminifera in the order Rotaliida. They are found in sediments of Early Cretaceous (Barremian) to the present.

Heterohelicoidea is a superfamily of middle Jurassic to Oligocene planktonic forams characterized by biserial or triserial tests, at least in the early stage, that may be reduced in the later stage but more commonly show chamber proliferation in the later stage. Aperture a low or high arch at the base of the final chamber or terminal in uniserial stage. Heterohelicoidea contains one family, the Heterohelicidae.

References

  1. Rotaliida, World Foraminifera Database, accessed 27 November 2018