Amphisorus hemprichii Ehrenberg

The genus Amphisorus belongs to a family of calcareous larger foraminifera, Soritidae (Ehrenberg 1839), whose members are common in shallow tropical and subtropical waters. Fossil samples of Amphisorus hemprichii Ehrenberg were found in Creteceous rocks (Ehrenberg. 1839 and 1840). Today, it shows a wide range of distribution in the Indo-Pacific and abundantly found in the Gulf of Aqabe to the north of the Red Sea (Reiss and Hottinger, 1984; Haunold et al., 1998). The benthic foraminifer A. hemprichii bears algal-symbionts. This symbiotic association provides it with the necessary energy to survive in oligotrophic environments (Hallock 1999). This symbiotic relationship also promotes exceptional test growth in foraminifers by enhancing calcification (ter Kuile 1991). A. hemprichii populations have been first recognized in June 2002 in sediment samples from few coves around Kalkan, Kas, and in Kekova (Antalya -SW Turkey). However, in two years it covered more than 100km coastline and is still spreading in the Aegean Sea, forming uncountably dense populations on the benthos (Figure 2). Most tests are l-2mm in diameter, but a small percentage of the population is between 0.5-1 mm. In some of the stations off Kas, much larger specimens are observed, reaching 1cm in diameter. Amphisorus hemprichii Ehrenberg specimens are observed at a depth range of 3-24 m, but most live between 8-18 m water depth. In Aegean waters, they are found epiphitically on Posidonia oceanica (Linné) Delile and Halophila stipulacea (Forsskâl) Ascherson. But, on the coasts of Kas and Kekova it is extremely abundant that they are observed not only macrophytes and phanerogams, but also on every kind of substrate, even on themselves (Figure 2).

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