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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.
Idalina is a genus of foraminifera included in the Hauerinidae, (Miliolida), that lived during the latter part of the Late Cretaceous.
Verbeekinidae are a family of large fusulinaceans characterized by subspherical, planispirally coiled tests and a long coiling axis. The wall is composed of a dense outer tectum and inner alveolar keriotheca. They are most prominent in Japan and Southeast Asia.
Involutinida is an order of foraminifera included in the Spirillinata found in the fossil record from the early Permian to early Late Cretaceous (Cenomanian).
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.
The Rzehakinidae is a family of Lower Cretaceous to recent formaminifera that resemble the calcareous imperforate Miliolidae but which are constructed of finely agglutinated material that veneers an organic base. Tests are with two, or less commonly three, chambers per whorl, which are commonly added in various planes. In form they are generally ovoid.
The Ammodiscacea is a superfamily of foraminifera in the order Textulariida. tests are made of agglutinated grains and consist of a proloculus followed by an enrolled tubular second chamber open at the distal end, that lacks internal septa but which may have growth constrictions.
The Hormosinacea is a superfamily of agglutinated foraminifera in the Textulariida, with a range that extends from the Middle Ordovician, that unites seven families characterized by multilocular tests,, in a uniserial arrangement.
Clavulina is a genus of aggulinated benthic foraminiferans with an elongate test. The early stage is triserial and triangular in section, the later stage uniserial and rectilinear, with angular to rounded section. In some species agglutinated walls have considerable calcareous cement. Septa are secondarily doubled as a result of imperforate floors, which are added as new chambers are formed. Walls contain fine bifurcating canaliculi within, openings of which are sealed internally by an inner organic lining, and externally by the imperforate surface layer of the wall. The aperture is interiomarginal in the early triserial stage, terminal and rounded in the adult.
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.
Sigmoilina is 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.
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.
Alfred R. Loeblich Jr (1914–1994) was an American micropaleontologist. He was married to Helen Niña Tappan Loeblich and the two co-authored a number of important works on the Foraminifera and related organisms.
Miliamminana is a subclass of miliolates established by Mikhalevich, 1980 that combines two groups of foraminifers with agglutinated tests. They are the Rzehakinidae which previously were included in the Texulariina in the Treatise on Invertebrate Paleontology although milioline in form, and the milioline Schlumbergerinida which includes genera removed from the Miliolina. The rzehakinids are composed of finely agglutinated material, insoluble in acid, over an organic base. Schlumbergerinids are composed of acid soluble agglutinated material over a porcelenous base. The unifying character is the nature of their coiling in which there are two tubular chambers, or sections, per whorl arranged in various planes and the fact that they are in part all agglutinated.
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.
Spirocyclina is a genus of large forams, with a flat test as much as 10mm in diameter. Coiling is planispiral to slightly asymmetric and mostly involute, some becoming uncoiled with a straight final stage. The final whorl, or stage, has about 25 strongly arcuate chambers. Composition is of agglutinated matter, the outer layer of the wall imperforate. Chambers are subdivided into secondary chamberlets by internal structures. The aperture consists of a double row of pores on the apertural face. Anchispirocyclina and Martiguesia are among related genera.
Anchispirocyclina is a genus of agglutinated discoidal forams known from the upper Jurassic to the lower Cretaceous of Europe, north Africa, USA and Cuba.
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.
Martiguesia is a genus of agglutinated benthic forams from the Upper Cretaceous (Santonian) of France. The test is free, the early stage planispirally coiled, becoming nearly straight during later growth. The agglutinated wall is externally imperforate, the interior with a coarse alveolar network. Chambers are subdivided and almost completely filled by irregular radial pillars. The aperture, cribrate.
References
- Alfred R. Loeblich Jr and Helen Tappan,1988. Forminiferal Genera and their Classification. e-book
- Alfred R. Loeblich Jr and Helen Tappan, 1964. Sarcodina Chiefly "Thecamoebians" and Foraminiferida; Treatise on Invertebrate Paleontology, Part C Protista 2. Geological Society of America and University of Kansas Press.
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