Таксономічна структура прибережного угруповання обростання, що формується чорноморською мiдiєю Mytilus galloprovincialis

Abstract

Peculiarities of the taxonomic structure of the coastal fouling community formed by the bivalve mollusk Mytilus galloprovincialis Lamarck, 1819 on the underwater surface of solid substrates located in the Odessa Bay of the Black Sea have been revealed. The qualitative composition, degree of occurrence, size characteristics and features of quantitative development of invertebrates of this community were determined. As part of the fouling community, 65 species of invertebrates belonging to 61 genera, 47 families, 22 orders, 10 classes and 6 types were identified. It was found that among the large taxa of the community Cnidaria, Annelida, Bryozoa, Arthropoda, Mollusca, Chordata, the most numerous species was the Arthropod type. Annelida and Mollusca accounted for one-fifth and one-fourth of all species. The other three types of invertebrates were represented by one or two species. A characteristic feature of the taxonomic structure of the community was that in most cases, each identified genus was represented by only one species, which in specific conditions was the most environmentally plastic representative of it. It is shown that the species structure of the fouling community was characterized by evident dominance of its edificator M. galloprovincialis. The maximum abundance of this species in the community was 11960 sp.·m-2, and biomass – 10328,6 g·m-2. In addition, 12 other invertebrates with 100 % occurrence were key-species of the community. These species, together with those with occurrence of more than 75 %, belonged to the characteristic species of the community. A total of 22 such species were identified. Among other invertebrates, 5 species (P = 50–75 %) were permanent, 8 species (P = 25–50 %) were rare, and 30 species (P <25 %) were random. The most of the organisms in the coastal fouling community of the Odessa Bay are eurybiont species was established. The presence in the fouling community invasive species of bivalve mollusks Arcuatula senhousia (Benson, 1842), which is systematically very close to the Black Sea mussel Mytilus galloprovincialis, was revealed. Due to its opportunistic properties, this mollusk poses a certain threat to the existence of settlements of aboriginal species of bivalve mollusks. The coastal fouling community formed by the Black Sea mussel has a certain degree of stability, as the same species of invertebrates remain characteristic of its taxonomic structure for 40 years.