MICROALGAE IN THE DIET OF EUCYPRIS MAREOTICA (CRUSTACEA, OSTRACODA) IN THE HYPERSALINE LAKE CHERSONESSKOYE (CRIMEA)

Abstract

In the Crimea, there are many hypersaline lakes and lagoons, where Eucypris mareotica (Ostracoda), high halotolerant species, inhabit. Despite the wide distribution of the species and the abundance of its populations, little is known about the biology of E. mareotica, including its nutrition. Diversity of microalgae in gut of E. mareotica in Lake Chersonesskoye was studied. The crustaceans ate both phytoplankton and alga, which growth on cladophora filaments, as well as various small animals, but microalgae played a main role in their nutrition. The proportion of individuals, which had algae in intestines, ranged in a sample from 0 to 93%. In 335 analyzed individuals, 22 species of microalgae were found, which belong to 4 types, 4 classes and 11 orders. Of these, 4 species belong to the type Cyanobacteria, 3 – to Myzozoa, 4 – to Haptophyta, 11 – to Ochrophyta. The most common species was Peridinium cinctum. Given the availability of a wide variety of consumed microalgae, ostracod gut content analysis can be used to assess species diversity of microalgae in the lakes.