First contours of autecology of freshwater heterotrophic euglenoids – results of two-year research on 18 freshwater bodies

Abstract

This study brings the first information about the autecological traits of heterotrophic euglenoids at eighteen localities in South Bohemia (Czech Republic). A number of environmental and landscape parameters including water chemistry and diversity of algae as well as of heterotrophic protists were analyzed over two years in order to assess the effect of environmental parameters on heterotrophic euglenoids. The major diversity of osmotrophs was found in acidic wetlands (i.e., peat bogs), while the majority of phagotrophs were detected in polytrophic sites. This was also illustrated by the correlation of heterotrophic euglenoids with other groups of organisms and other biotic parameters related to the trophic level at the sampling sites. Apparently, habitats with well-developed macrovegetation harboured the highest alpha diversity of heterotrophic euglenoids. Noteworthy, most taxa were found during summer and fall. Additional ecological data on rarely reported taxa observed during this survey (Astasia lagenula var. maxima, Calycimonas quinquecarinata, Euglenopsis vacuolata, Heteronema proteus, Heteronema tremulum, Parmidium circulare) were provided as well.