| Summary: | Foraminifera are unicellular eukaryotic organisms that live individually autonomous in the sea (Hottinger, 2005). They form mechanically resistant tests, either by gluing material found in the environment or by secreting organic or calcareous shells. Along with the test, main characteristic of foraminifera are their pseudopodia emerging from the cell body through multiple apertures. Foraminifera are extremely abundant in marine sediments, which makes them useful in recent and fossil paleoenvironmental studies. The first simple forms of foraminifera appeared in Cambrian and since provide a long and well recorded evolutionary record throughout Paleozoic, Mesozoic and Cenozoic (BouDagher‐ Fadel, 2008). Based on life strategy, foraminifera are divided in two groups: benthic and planktonic foraminifera. Planktonic foraminifera passively float through the waters of open oceans moved by currents. Benthic foraminifera live on the sea floor; on the surface, buried into the sediment, or attached to plants, rocks or sediment particles. Based on their size and internal morphological structure benthic foraminifera can be divided into two groups; smaller and larger benthic foraminifera. The main criteria for identifying LBF is the complex internal structure which evolved to efficiently host photosymbionts, the key elements in the ecology of LBF. The symbiotic algae utilize the waste product of the foraminifera, allowing them to efficiently recycle of nutrients and to facilitate calcification (Ross, 1974; Leutenegger, 1984). This life strategy, LBF as a greenhouse, limits their occurrences to photic zone since algal symbionts are dependent on light for photosynthesis (Leutenegger, 1984). Besides light levels, the distribution and abundance of LBF is determined by relatively well‐known parameters, including hydrodynamic energy, water temperature, salinity, food availability and substrate type (Hottinger, 1983; Hohenegger, 1994; Renema, 2006). Therefore, the assemblage composition of fossil LBF can provide important and valuable ...
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