Pelagic ciliated protozoa in two monomictic, southern temperate lakes of contrasting trophic state: seasonal distribution and abundance

Two lakes of contrasting trophic state in the central North Island of New Zealand were sampled monthly for protozoan ciliates and potential food resources. Oligotrichs dominated numbers in both lakes. Subdominants in oligotrophic Lake Taupo included Askenasia, Pscudobalanion and Urotri-cha, and in eutrophic Lake Okaro Prorodon, Coleps, Urocentrum, Stentor and Spirostomum were important. Biomass was dominated by large predatory ciliates and Stentor in Lake Taupo, and Prorodon and Stentor in Lake Okaro. The importance of Prorodon and Stentor to ciliate biomass is unusual and has not been reported for northern hemisphere lakes. Small ciliates (