In view of frequent findings of the alien North American rotifer Kellicottia bostoniensis (Rousselet, 1908) in water bodies and watercourses of Russia, the generalization of information about its loca

Сообщества зоопланктона средней речной части Чебоксарского водохранилища и факторы, влияющие на формирование их видовой структуры

The article describes the features of the spatial distribution of zooplankton communities in the waters of the Pustynskaya lake-river system. The abundance of two related species of genus Kellicottia, the alien Kellicottia bostoniensis (Rousselet, 1908) and the indigenous K. longispina (Kellicott, 1879), was analyzed in some communities in 2013–2017. The greatest abundance of the alien species was noted in zooplanktic communities of mesotrophic water bodies (Seryozha River and Lake Svyato). It was found that, after the period of mass development of K. bostoniensis in 2013–2014, which could have been due to the initial stage of establishment of the alien species, its abundance sharply decreased. In 2013–2014, the abundance of the indigenous species K. longispina (Kellicott, 1879) was significantly lower than that of the alien species. Rotifer K. longispina dominated in the Protoka and Lake Svyato in 2017. The highest density of both species was found in the metalimnion of the mesotrophic Lake Svyato. A statistically significant positive correlation was found between the abundance of K. bostoniensis and the water temperature, transparency, and pH, as well as the abundance of predatory zooplankton species. The abundance of the native species K. longispina correlated negatively only with the value of water pH.

The hydrobiological studies carried out in 2017 and 2018 yielded new information on the distribution of the alien species Kellicottia bostoniensis(Rousselet, 1908), discovered in five...

The morphological characteristics of the North American invasive species Kellicottia bostoniensis Rousselet, 1908 were studied in 29 various types of water bodies and watercourses of the Middle Volga basin. The water bodies, which are the habitats of K. bostoniensis, are located on several territories that differ significantly in a set of characteristics, such as their geological structure, relief, climate, anthropogenic impact, hydrochemical and hydrophysical indicators, etc. The sizes of K. bostoniensis individuals in most of the studied water bodies and watercourses were measured and analyzed for the first time. A high positive correlation was found between the total body length and the posterior spine length (R2 = 0.79, p < 0.01), as well as the anterior spine length (R2 = 0.75, p < 0.01). A relationship was revealed between the lengths of the anterior and posterior spines (R2 = 0.58, p < 0.01). K. bostoniensis individuals in the studied water bodies and watercourses are characterized by large sizes, the median values of the total body length being 236–440 μm. These sizes are similar to those of individuals in the native habitats of North America and some biotopes of Europe and European Russia. Among the previously studied water bodies of Russia and other countries (Belarus, Sweden, Finland, Brazil, and Argentina), where researches of the morphological variability of K. bostoniensis were carried out, the largest body sizes were characteristic for the invader species of the Sura River. Larger K. bostoniensis specimens live in deep mesotrophic water bodies with high transparency, compared with representatives of this species in shallow eutrophic water bodies with less transparency in the Middle Volga basin. Our data on the morphological characteristics of the invading species of water bodies in the Middle Volga basin significantly expand the existing information on the morphological variability of K. bostoniensis individuals and their dependence on environmental factors.