foraminifer

plural foraminifers

1. Any of a large group of aquatic amoeboid protists of the subphylum Foraminifera, characterized by streaming granular ectoplasm that among other things is used for catching food, often with a calcareous shell with many holes through which pseudopodia protrude.

   The Heterostegina-bed at Malta is not without smaller Foraminifers (some of which we can identify,—as the Globigerina bulloides, Truncatulina lobatula, &c.), but the matrix is too stubborn to yield all its treasures.

   1860 January 4, T[homas] Rupert Jones, W[illiam] K[itchen] Parker, “3. On the Rhizopodal Fauna of the Mediterranean, Compared with that of the Italian and Some Other Tertiary Deposits.”, in The Quarterly Journal of the Geological Society of London, volume XVI, part I (Proceedings of the Geological Society), London: Longmans, Green, Longmans, and Roberts […], →ISSN, →OCLC, page 300

   5 more examples

   The species of foraminifer which composes, almost to the exclusion of all others, the deep Atlantic mud, is called Globigerina. […] The natural home of the foraminifers appears to be in the deeper parts of the ocean, commencing where the regular inhabitants of limited depths terminate.

   1859 October, “Art. V.—Physical Geography of the Atlantic Ocean.”, in The Westminster Review, American edition, volume LXXII, number CXLII, New York, N.Y.: Leonard Scott & Co., […], →OCLC, page 263

   From a palæontological point of view the only part of a Foraminifer with which we have to deal is the shell or "test," […] Each bud of the compound Foraminifer is surrounded by its own shell, so that the whole comes to be composed of a number of chambers, each containing a mass of sarcode.

   1872, Henry Alleyne Nicholson, “Sub-kingdom I.—Protozoa.”, in A Manual of Palæontology for the Use of Students […], 3rd edition, Edinburgh; London: William Blackwood and Sons, →OCLC, part II, page 61

   The environmental significance of foraminifer abundance variations in Arctic cores is controversial[…]. One interpretation concludes that foraminifer-rich intervals represent interglacial conditions reflecting seasonally absent or reduced ice cover leading to increased productivity; intervals barren or nearly barren of foraminifers are considered to represent glacial conditions with thicker ice cover and lower productivity[…].

   1994, Richard Z. Poore, Scott E. Ishman, R. Lawrence Phillips, David H. McNeil, “Paleoceanography”, in Quaternary Stratigraphy and Paleoceanography of the Canada Basin, Western Arctic Ocean […] (U.S. Geological Survey Bulletin; 2080), Washington, D.C.: United States Government Printing Office, →OCLC, page 10, column 1

   A cross-section through a single agglutinated foraminifer – in this case, one that selected both carbonate and non-carbonate grains to build its test. These foraminifers are recognizable by the chamber-shaped grain arrangements rather than the otherwise random distribution of grains in the rest of the rock.

   2003, Peter A. Scholle, “Grains: Skeletal Fragments: Foraminifers”, in A Color Guide to the Petrography of Carbonate Rocks: Grains, Textures, Porosity, Diagenesis (AAPG Memoir; 77), Tulsa, Okla.: American Association of Petroleum Geologists, →ISBN, page 37

   One of the most frequently asked questions concerns the predators of planktic foraminifers. Whereas a large variety of predators of benthic foraminifers have been identified, the nature of planktic foraminifer predators is largely enigmatic.

   2017, Ralf Schiebel, Christoph Hemleben, “Nutrition, Symbionts, and Predators”, in Planktic Foraminifers in the Modern Ocean, 2nd edition, Berlin; Heidelberg: Springer Nature, →DOI, →ISBN, section 4.6 (Predation), page 154, column 1

   Synonyms: foram, foraminifera, foraminiferan, foraminiferid, foraminiferon, foraminiferum