A Record of the Tropical Species Thermocyclops taihokuensis Harada, 1931 (Copepoda: Cyclopoida) in European Russia

• Published in: Biology bulletin of the Russian Academy of Sciences 2020-12, Vol.47 (10), p.1347-1350
• Main Authors: Zhikharev, V. S., Gavrilko, D. E., Shurganova, G. V.
• Format: Article
• Language: English
• Subjects: Biochemistry; Biomedical and Life Sciences; Cell Biology; Copepoda; Cyclopoida; Ecology; Introduced species; Life Sciences; Migratory species; Phenotypic plasticity; Rivers; Short Communications; Thermocyclops; Tropical environment; Zoology
• ISSN: 1062-3590; 1608-3059
• DOI: 10.1134/S106235902010026X

—In July 2018, in the estuary of the Sura River (a tributary of the first order of the Cheboksary reservoir, Nizhny Novgorod oblast, Russia), a tropical exogenous copepod Thermocyclops taihokuensis Harada, 1931 (Copepoda: Cyclopoida) was found. Information on the finding of this species in the European part of Russia is extremely scarce. There is only one report of a finding of this species in the lower reaches of the Volga River. The main habitat of T. taihokuensis is in East and Central Asia, as well as tropical regions. This paper presents a brief description of T. taihokuensis with updated drawings. The T. taihokuensis females registered in the estuarine area of the Sura River had an average size of 1060 ± 20 μm. The spread of tropical crustaceans beyond their natural habitat appears to be linked to human activities and the transport of ballast water by ships. In addition, the concept of zoochoria suggests that the settlement of this species may be associated with the transfer of T. taihokuensis at the resting stages by migratory species of waterfowl. Thus, migration routes of various bird species from the Arctic and temperate climatic zones to subtropical and tropical regions cross the European part of Russia. Alien species have high phenotypic and ecological plasticity and are able to cause imbalances in ecosystems. Therefore, new studies of the Sura River and the Cheboksary reservoir will help not only to assess the success of the naturalization of T. taihokuensis , but also to estimate the environmental consequences of the penetration of this species into the territory of the European part of Russia.