New finds of naked amoebae

Findings of naked amoebae in various habitats of Ukraine and other territories are presented. Saccamoeba sp., Thecamoeba similis (Greeff, 1891) Lepşi, 1960, Vexillifera bacillipedes Page, 1969, Vannella lata Page, 1988, Acanthamoeba sp., Willaertia magna De Jonckheere, Dive, Pussard & Vickerman, 1984 were identified based on morphological data and molecular genetic research methods. All these species of amoebae are characterized according to our own observations and measurements and the published data. The amoebae we found belong to three classes (Tubulinea, Discosea, Heterolobosea), six orders (Euamoebida, Thecamoebida, Dactylopodida, Vannellida, Centramoebida, Schizopyrenida), six families (Hartmannellidae, Thecamoebidae, Vexilliferidae, Vannellidae, Acanthamoebidae, Vahlkampfiidae) and six genera (Saccamoeba, Thecamoeba, Vexillifera, Vannella, Acanthamoeba, Willaertia). W. magna was the least common in water bodies of different regions of Ukraine; Saccamoeba sp., V. bacillipedes in the studied water bodies are either uncommon species or occupy the middle position in terms of frequency of occurrence In the water bodies of Ukraine T. similis, V. lata, Acanthamoeba sp. are both the least common and the most common species, or occupy the middle position in terms of frequency of occurrence. The following ecological groups of naked amoebae have been identified in relation to temperature: eurythermal, psychrophilic stenothermal, thermophilic stenothermal. In relation to the concentration of dissolved oxygen in water: euryoxidic and stenooxidic. Three species of amoebae can withstand either a wide range of values of organic substances dissolved in water, or belong to stenobiont species. The recorded amoebae belong to monotactic (Saccamoeba sp.), striate (T. similis), dactylopodial (V. bacillipedes), fan-shaped (V. lata), acanthopodial (Acanthamoeba sp.) and eruptive (W. magna) morphotypes.