Nummulites


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Related to Nummulites: Nummulitidae

Nummulites

[′nəm·yə‚līts]
(invertebrate zoology)
A genus of unicellular shelled protozoa of the order Foraminiferida (superfamily Nummulitacea, family Nummulitidae). The discoidal, lenticular, or globular test or shell can reach a diameter of about 5 inches (12 centimeters) and is composed of finely perforate calcium carbonate, it consists of planispirally enrolled whorls of many tiny undivided chambers.

Nummulites

 

a genus of extinct unicellular organisms of the subclass Foraminifera. Remains of Nummulites have been found in Upper Cretaceous and in Paleogene deposits in the tropics and subtropics of Europe, Asia, Africa, and America. Nummulites had a lenticular or discoid shell with a diameter that ranged from 1 to 16 cm. The shell contains many whorls divided by septa into chambers; each new whorl completely overlaps the next older whorl. Nummulites led a benthopelagic mode of life. Aggregates of their shells formed nummulitic limestone, which is used as a building material. Nummulites are important index fossils in the stratigraphy of the Paleogene.

REFERENCE

Osnovy paleontologii: obshchaia chast’: prosteishie. Moscow, 1959.
References in periodicals archive ?
(1846): Memoire sur le terrain a Nummulites (Epicretace) des Corbieres et de la Montagne Noire.
ii) Nummulites atacicus: This species was dominantly found in the lower to middle parts of the formation throughout the study area.
The presence of large nummulites and lepidocyclinids represents that this microfacies took place in relatively deep water and was formed in the lower photic/oligophotic zone in the distal middle ramp [35,36,43,53,33,32, 30,50,56,11,48,9,10,57].
Nummulites, Assilina and Discocyclina are mostly present in the open shoal to the offshore part of the carbonate platform.
Nummulites striatus appear first in SBZ 18 and ranges to lower part of SBZ 19, whereas later it was also recorded from SBZ 17 of Turkey and Romania (Rusu et al., 2004; Ozcan et al., 2010).
4a).in this microfacies a subfacies has been identified, namely Nummulites /Orbitolites bioclast pelloidal packstone.
Nummulites mamillatus (FICHTEL and MOLL) Nummulites atacicus LEYMERIE 1846
We can define an Acme zone equal to SB13 base on presence of index LBF fossils of nummulites. Time of formation is from 47.47 to 45.35 Ma.
Other associated species include Discocyclina dispansa, and species of Austrotrillina, Nummulites, Fabiania , Alveolina, Amphistegina, Asterigerina, Operculina, Smoutina, Assilina, Dictyoconus, Orbitolites, Elphidium and Planorbulina (Figs.
In the fossil record Alveolina is found in association with Nummulites and Orbitolites in the Eocene Jdeir Formation of offshore Libya representing a back ramp environment (Anketell and Mirheel 2000).