Abadehella

Last updated

Abadehella
Temporal range: Lopingian
Scientific classification
Domain:
(unranked):
SAR
(unranked):
Superphylum:
Phylum:
Order:
Superfamily:
Family:
Abadehellidae
Genus:
Abadehella

Okimura & Ishii, 1975

Abadehella is a genus of large Upper Permian benthic forams in the order Fusulinida. [1] It is the sole known genus of the family Abadahellidae, for which the diagnosis is the same. Abadahellidae was established by Loeblich and Tappan 1984; Abadahella by Okimura and Ishi, 1975.

Contents

The genus extends across the lowermost member of the Zewan Formation in Kashmir, the Palaeofusulina limestone in Malaysia, the Lepidolina multiseptata limestone in Cambodia and the Lepodlina mustipetata and Lepidolina kumaensis Zones in Japan.

Physiology

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.

See also

Related Research Articles

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

Parafusulina is a genus of foraminifera included in the fusulinacean family Schwagerinidae that were extant during the Permian.

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

The Nodosinellacea is a superfamily of fusulinids in which the test is of one or more distinct chambers with the wall single layered or with a microgranular outer layer and fibrous inner layer. Differs from the Geinitzinacea in that the latter has the layers reversed.

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.

<span class="mw-page-title-main">Lagenida</span> Order of single-celled organisms

Lagenida is an order of benthic foraminiferal protists in which the tests (shells) are monolamellar, with walls composed of optically and ultra-structurally radiate calcite, with the crystallographic c-axes perpendicular to the surface. Lagenids first appear in the Upper Silurian and continue to the Recent. They are currently divided into two superfamilies, the older Robuloidacea which range from the Upper Silurian to the Lower Cretaceous (Albian) and the younger Nodosariacea, ranging from the Permian to Recent.

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.

<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.

Discorbis is a genus of benthic Foraminifera, 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.

Fabiania is a genus of large fossil benthic calcareous forams with a range extending from the Upper Paleocene to the Upper Eocene.

Buccella is a genus of late Cenozoic benthic foraminifera that made its first appearance during the Oligocene and is found living in recent oceans.

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.

<i>Geinitzina</i> Extinct genus of single-celled organisms

Geinitzina is a genus of Foraminifera from the early Carboniferous (late Mississippian to the late Permian that may have extended into the Triassic. Chambers are uniserial, arranged in a single row, or line. Test wall is double layered. The outer layer is of hyaline radial calcite, and is light in color. The inner layer is of microgranular calcite, and is dark is color. Both layers are secreted by the protoplasm.

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.

The Ventrolaminidae are a family of benthic Foraminifera included in the Involutinida, now part of the subclass Spirillinana, class Spirillinata.

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.

<span class="mw-page-title-main">Foraminifera test</span> Shell of a particular type of protist

Foraminiferal tests are the tests of Foraminifera.

References

  1. BouDagher-Fadel, M.K. (2008). Evolution and Geological Significance of Larger Benthic Foraminifera (1st ed.). Burlington: Elsevier. ISBN   9780080931753.

Memoirs of the Faculty of Science, Kyoto University: Series of geology and mineralogy, Volumes 45–48. 12 Jan 2011