Description of <i>Tetrahymena empidokyrea</i> n.sp., a new species in the <i>Tetrahymena pyriformis</i> sibling species complex (Ciliophora, Oligohymenophorea), and an assessment of its phylogenetic position using small-subunit rRNA sequences

Abstract

Ciliates infected 0.25% of adult Aedes sp. mosquitoes collected in Guelph, Ontario. Morphological observations of live and stained specimens indicated that these ciliates belonged to the Tetrahymena pyriformis sibling species complex. This study provides the first well-documented case of insects being infected by a species in the T. pyriformis complex. Mating experiments demonstrated that these "mosquito" ciliates were reproductively isolated from previously described biological species in the complex, and are designated a new species, Tetrahymena empidokyrea n.sp. Phylogenetic analysis using SSrDNA sequences suggested that T. empidokyrea n.sp. is either basal to all species in the genus Tetrahymena or basal to one of the two main lineages in that genus.