The First Finding of Radiolaria Arachnocorys circumtexta Haeckel, 1860 and the Bottom Microalgae in Brown Alga Cystoseira barbata (Stackhouse) C.A. Agardh Epiphyton (Crimea, Black Sea)

Abstract

The planktonic species Radiolaria of Arachnocorys circumtexta Haeckel, 1860 (Radiolaria, class Nasseillaria, family Lophophaenidae Haeckel, emend. Petrushevskaya, 1971) in the epiphyton of the brown alga Cystoseira barbata (Stackhouse) C.A. Agardh in August 2002 in Martynov Bay (Sevastopol, Crimea) at a depth of 2.5 m at a water temperature of 24.4°C and a salinity of 18‰ was the first time in the Black Sea. Before, this species was indicated by E. Haeckel in the Mediterranean Sea plankton. For the Black Sea, this species is probably invasive. The sizes of Radiolaria blacksea specimens the correspond to the literature data. In addition to Radiolaria and microalgae have been found in the epiphyton of C. barbata, including 14 species of Bacillariophyta and one species of Dinophyta from the genus Prorocentrum Ehrenb. Marine species predominate (67%) and 53% of all species encountered are β-mesosaprobionts – indicators of moderate organic water pollution. 33% of cosmopolites are found in all geographical zones from the Arctic to the Antarctic waters. The aim of this report is presentation of new information about a rare modern Radiolaria and the taxa of benthic microalgae Cystoseira barbata epiphyton from the Black Sea.