Foraminifera are members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly an external shell of diverse forms and materials. Tests of chitin are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment, while a smaller variety float in the water column at various depths. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA.
Parafusulina is a genus of foraminifera included in the fusulinacean family Schwagerinidae that were extant during the Permian.
Carterina is a genus in the Foraminifera. It is the only known genus of the order Carterinida and family Carterinidae. 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.
Discorbacea, Discorboidea in recent taxonomies, is a superfamily of foraminifera,, with a range extending from the Middle Triassic to the present, characterized by chambers arranged in a low trochspiral; an umbilical or interiomarginal aperture, with or without supplementary apertures; and a wall structure that is optically radial.
Abadehella is a genus of large Upper Permian benthic forams in the order Fusulinida. The 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.
The Robertinida are an order of Middle Triassic to recent, benthic foraminifera in which tests are planispirally to trochospirally coiled, with chambers provided with an internal partition and hyaline perforated walls composed of optically radiated aragonite.
Discorbis is a genus of benthic Foraminfera, that made its first appearance during the Eocene. Its present distribution is cosmopolitan.
Astrononion is a genus of foraminifera in the family Nonionidae, characterized by an evolute planispiral test with radially stellate structures partly covering the sutures on either side. The test is free, bilaterally symmetrical; periphery broadly rounded; chambers distinct, separated by depressed radial sutures, increasing gradually in size, and usually inflated; aperture a low arched opening at the base of the face of the test. The wall is of finely perforate monolamellar granular calcite.
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 Cassidulinidae is a family of Paleocene to recent benthic foraminifera that make up part of the rotaliid superfamily Cassidulinacea, characterized by calcareous test with biserially arranged chambers in a planispiral coil, at least in the early stage, but which later may uncoil.
Kalosha is a genus of foraminifera included in the miliolid family Spiroloculinidae. Its test is small, ovate in outline, only up to 0.2 mm in the greatest dimension; begins with an oval proloculus followed by planispirally coiled elongate tubular chambers one-half coil in length, forming three to five whorls. The wall is calcareous, hyaline (glassy), and imperforate. The aperture is a narrow slit at the end of the final chamber.
Schwagerina is an extinct genus of fusulinacean Foraminifera that is used as an Early Permian index fossil. The overall shape of the shell or test is fusiform to subcylindrical, the spirotheca, or outer test wall, is thick, and composed of tectum and alveolar keriotheca; the septa are fluted throughout the length of the shell, intense to top of chambers in some, only in lower parts in others; axial fillings highly variable, chomata distinct or thin and discontinuous.
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.
Sigmoilinita is a miliolid genus (Foraminifera) with an ovate to fusuform test that becomes flattened with growth. Chambers are tubular, one-half coil in length, at first added in a sigmoiline (S-shaped) series starting at slightly more than 180° apart. the angle gradually decreasing until the later whorls are planispiral. Chambers are numerous, the wall narrow. imperforate, porcelaneous. The aperture at the end of the final chamber. may have a weakly developed tooth
Sigmoilinopsis is a genus of miliolid Foraminifera, with an ovate test, chambers one-half coil in length, arranged in rapidly changing planes in the early stage resulting in two spiralling series that appear sigmoid in section, gradually becoming planispiral in the adult. Walls are thick, porcelaneous but enclosing a large quantity of agglutinated quartz particles, sponge spicules, and shell fragments; the aperture terminal, rounded, with a small tooth.
Triloculinella is a genus of Miliolacean forams with a fusiform to asymmetrically globular test. Inner chambers, one-half coil in length, are crypto-quinqueloculine to quinqueloculine in arrangement; The final three to five visible from the exterior. The aperture is an arch at the end of the final chamber, largely covered by a broad apertural flap, which distinguishes the genus from Triloculina, Quinqueloculina and such, characterized by a more narrow tooth. The wall, as for all miliolids, is calcareous, imperforate, porcelaneous.
Miliollata is a class wherein Foraminifera is regarded as a phylum that unites the porcelaneous Miliolida, and siliceous Rzehakinidae based on similarities of their tests. Previously the Rzehakinidae were included in the Textulariina based on test wall composition rather than test form. The meaning of Miliolida is retained.
Miliolana is a subclass established by Saidova, 1981 that comprises porcelaneous members of the Miliolata from the Cornuspirida, Miliolida with agglutinated forms removed to the Miliamminana, and Soritida. Included are both free and attached forms, some coiled with two chambers per whorl arranged in different planes, others that are irregular or have serial chambers, and still others are fusiform with complex interiors, superficially resembling the Fusulinacea. The unifying character is their imperforate porcelaneous tests.
Chilostomelloidea is a superfamily of foraminifera in the order Rotaliida. They are found in sediments of Early Cretaceous (Barremian) to the present.
