Macroalgal Fouling of Shells of Rapana venosa (Valenciennes, 1846) (Gastropoda, Muricidae) in the Northern Black Sea

Algal fouling of a gastropod predatory species Rapana venosa (Valenciennes, 1846) was investigated. R. venosa shells act as substrate for a great number of different fouling organisms, among which macroalgae are the most important. We studied the fouling communities on two ecomorphs (sandy and rocky) of R. venosa from the northern part of the Black Sea from 2008 to 2017. The fouling algae taxa were listed and the frequency of their occurrence on two ecomorphs of R. venosa was determined. 65 algae species were found, namely Chlorophyta – 20, Ochrophyta – 16 and Rhodophyta – 29 species. Typical alga species of sandy and rocky R. venosa ecomorphs and their assemblages’ composition was featured. It was found that the expansion of algae species distribution on the soft substrate is associated with R. venosa . During the period of R. venosa populations’ development this invasive species has become an important element of the Black Sea ecosystem which contributes to saving biological diversity of the benthic community due to formation and spreading of its consortium complexes.