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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, dominated by the shells of planktonic forms.
The Allogromiida is an order of single-chambered, mostly organic-walled foraminiferans, including some that produce agglutinated tests (Lagynacea). Genetic studies indicate that some foraminiferans with agglutinated tests, previously included in the Textulariida or as their own order Astrorhizida, may also belong here. Allogromiids produce relatively simple tests, usually with a single chamber, similar to those of other protists such as Gromia. They are found as both marine and freshwater forms, and are the oldest forms known from the fossil record.
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.
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.
The Textulariida are an order of foraminifera that produce agglutinated shells or tests. An agglutinated test is one made of foreign particles glued together with an organic or calcareous cement to form an external shell on the outside of the organism. Commonly, the order had been made up of all species of Foraminifera with these types of shells, but genetic studies indicate these organisms do not form an evolutionary group, and several superfamilies in the order have been moved to the order Allogromiida. The remaining forms are sometimes divided into three orders: the Trochamminida and Lituolida, which have organic cement, and the Textulariida sensu stricto, which use a calcareous cement. All three orders or superfamilies are known as fossils from the Cambrian onwards.
Carterina is a genus in the Carterinida. The type species is Carterina spiculotesta Brady, 1884. The genus is described from specimens gathered during the Challenger expedition's circumnavigation of the Earth from 1872-1876.
The Spirillinida are an order of foraminifera in which the test, or shell, primitively consists of an enrolled open tube, coming after the proloculus, wound planospirally or conically, commonly composed of an optically single crystal of calcite. The aperture is a simple opening at the end of the tube. Advanced forms with more than one chamber may consist of a few crystals, or rarely, a mosaic of crystals of calcite.
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.
Nodosariacea is one of two superfamilies making up the foraminiferal order Lagenida. The other being the Robuloidacea. Of these two Nodosariacea is the more advanced, as well as being the younger.
Involutinida is an order of foraminifera included in the Spirillinata found in the fossil record from the early Permian to early Late Cretaceous (Cenomanian).
Cibicides is a genus of cosmopolitan benthic foraminifera known from at least as far back as the Paleocene that extends down to the present.
Discorbis is a genus of benthic Foraminfera, that made its first appearance during the Eocene. Its present distribution is cosmopolitan.
Rosalina is a genus of foraminifera included in the rotaliid family Rosalinidae.
The Cassidulinacea is a superfamily of benthic amoeboid foraminifera in the order Rotaliida that has been extant from the Paleocene down to the present. Tests are composed of secreted, optically radial or granular, perforate calcite with chambers biserially coiled at least in the early part, Apertures are usually an interiomarginal slit, but may become terminal and may have secondary features.
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.
Triloculina is a genus of foraminifera in the order Miliolida, included in the Quinqueloculininae. The test is three, chambers each a half coil in length. Early chambers, at least in the microspheric generation, in quinqueloculinan arrangement, later becoming triloculine with successive chambers added in planes 120 degrees apart. Only the final three chambers are visible externally. The aperture is terminal, at the end of the final chamber, with a bifid tooth in adult forms. As with the entire order, the test is composed of imperforate, porcelaneous calcite.
Sigmoilina ia a miliolid genus, referring to the foraminiferal order Miliolida, characterized by an assymmetricall biconvex test formed by strongly overlapping chambers, one-half coil in length, that form a sigmoid (S-shaped) curve in cross section. The strongly overlapping chambers obliterate earlier ones from view resulting in the compressed biloculine appearance, differing from the squat, depressed biloculine form of Pyrgo and Biloculina. The test, as for all Miliolida, is porcelaneous and imperphorate, the terminal aperture, with tooth, the only point of egress and ingress for the animal.
Hauerinidae is a large and diverse family of miliolid forams that includes genera distributed among various subfamilies in the Treatise as well as genera named and described since.
Haurania is a genus of elongated, finely agglutinated benthic foraminifera included in the Spirocyclinidae. The test is free, starting with a brief planispiral coil followed by a straight uncoiled stage. The exterior is imperforate, the interior divided by radial septula or beams, perpendicular to the septa and outer wall. The aperture is cribrate, a series of openings on the terminal face.
Chilostomelloidea is a superfamily of foraminifera in the order Rotaliida. They are found in sediments of Early Cretaceous (Barremian) to the present.
References
- Gupta, Barun K. Sen (2002). Modern Foraminifera. Springer. pp. 16–. ISBN 978-1-4020-0598-5.
- Planorublinacea, Loeblich & Tappan, 1988.
- Loeblich, Alfred R.; Tappan, Helen (1964). Moore, R.C. (ed.). Protista 2: Sarcodina Chiefly "Thecamoebians" and Foraminiferida. Treatise on Invertebrate Paleontology. C (5th ed.). Geological Society of America. ISBN 978-0-8137-3003-5.