|
Rotaliida
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. In form, rotaliid tests are typically enrolled, but may be reduced to biserial or uniserial, or may be encrusting with proliferated chambers. Chambers may be simple or subdivided by secondary partitions; the surface is smooth, papillate, costate, striate, or cancellate; the aperture is simple or with an internal toothplate, entosolenian tube, or hemicylindrical structure; it may have an internal canal or stolen systems. Rotaliids are primarily oceanic benthos, although some are common in shallower estuarine waters. They also include many important fossils, such as the nummulitids. Taxonomy The Rotaliida are now divided into the following superfamilies: [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and other uses; and commonly an external shell (called a "Test (biology), test") of diverse forms and materials. Tests of chitin (found in some simple genera, and Textularia in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthos, benthic), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. 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. Foraminifera typically produce a test (biology), test, or shell, which can have eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acervulinacea
Acervulinacea is a superfamily in the Foraminifera order Rotaliida 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. In form, rotaliid tests are typically enrolled, but ma .... 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. The Acervulinacea contains two families with living genera, the Acervulinidae of Schultze, 1854 and the Homotrematidae of Loeblich and Tappan, 1964. The Acervulinidae are characterized by a free or attached test with an early spiral stage followed by spreading chambers in one or more layers. The range is from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chilostomellacea
Chilostomelloidea is a superfamily of foraminifera in the order Rotaliida. They are found in sediments of Early Cretaceous (Barremian The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 129.4 ± 1.5 Ma (million years ago) and 121.4 ± 1.0 Ma). It is a subdivision of the Early Cretaceous Epoch (or Lower Cretaceous Series). It is preceded ...) to the present. The test, or shell, may be trochospiral to planispiral throughout, or just in the early part with the later part uncoiled. Chambers may be somewhat enveloping, and attached forms may uncoil in the adult. In coiled forms, the aperture is interiomarginal, or terminal in uncoiled forms. The test wall is of perforate hyaline (glassy) oblique calcite, appearing optically granular. Subtaxa The superfamily Chilostomelloidea consists of the following families: References Foraminifera superfamilies Rotaliida {{Foraminifera-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterigerinacea
The Asterigerinacea (or Asterigerinoidea) is a superfamily of Foraminifera included in the order Rotaliida, proposed by Loeblich and Tappan in 1988.Loeblick A.R. and Tappan H,1988. Forminiferal Genera and their Classification. (e-book) GSI The Asterigerinacea unites three families, the Episomariidae and Asterigerinidae which had been included in the Discorbacea and the Amphisteginidae which was included in the Orbiotoidacea in the Treatise on Invertebrate Paleontology, Part C.Loeblick A.R. and Tappan H.1964. Sarcodina Chiefly "Thecamoebians" and Foraminiferida. Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ..., part C Protista 2. Geological Society of America and University of Kansas Press. Asterigerinacea are characterized by a trochospi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discorbacea
Discorbacea, Discorboidea in recent taxonomies, is a superfamily of foraminifera, Loeblich and Tappan,1988Forminiferal Genera and their Classification (testate protists), 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.Loeblick and Tappan,1964. Sarcodina Chiefly "Thecamoebians" and Foraminiferida; Treatise on Invertebrate Paleontology, part C Protista 2Sen Gupta, 2002. Modern Foraminifer Pub Springer Eight families are currently recognized, further characterized here in. * Discorbidae – Discorbacea in which each chamber is partly divided by an imperforate wall and the umbilical area partly is covered by chamber extensions. '' Discorbis'', '' Neoeponides'' * Bagginidae – Discorbacea with an overall finely perforate test, but imperforate in a part of ventral side '' Baggina'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globigerinina
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. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nummulite
A nummulite is a large lenticular fossil, characterized by its numerous coils, subdivided by septa into chambers. They are the shells of the fossil and present-day marine protozoan ''Nummulites'', a type of foraminiferan. Nummulites commonly vary in diameter from 1.3 cm (0.5 inches) to 5 cm (2 inches) and are common in Eocene to Miocene marine rocks, particularly around southwest Asia and the Mediterranean (e.g. Eocene limestones from Egypt). Fossils up to six inches wide are found in the Middle Eocene rocks of Turkey. They are valuable as index fossils. The ancient Egyptians used nummulite shells as coins and the pyramids were constructed using limestone that contained nummulites. It is not surprising then that the name "''Nummulites''" is a diminutive form of the Latin '' nummulus'' meaning "little coin", a reference to their shape. In 1913, naturalist Randolph Kirkpatrick published a book, ''The Nummulosphere: an account of the Organic Origin of so-called Igneous Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
