Number of records in different observation periods.

 
  Part of: Mukhortova O, Senator S, Unkovskaya E (2021) Distribution and species composition of zooplankton (rotifers and crustaceans) in the Basin of the Middle Volga River, Russia. Biodiversity Data Journal 9: e76455. https://doi.org/10.3897/BDJ.9.e76455