Molecular and Morphological Delimitation of Species in the Group of Lepocinclis Ovum-like taxa (Euglenida).

Although Lepocinclis ovum is recognized as a cosmopolitan and common species, and Lepocinclis globulus is the type species of the genus Lepocinclis, their correct identification is nearly impossible. The reason is that over 30 morphologically similar taxa appear in the literature, but no good diagnostic features exist to distinguish amongst them. Using environmental sampling and nuclear SSU rDNA sequencing, we delimited species within the group of Lepocinclis ovum-like taxa. Morphological and molecular features were analyzed for taxa isolated from Poland and six cultured strains from algal collections. In the case of environmental sampling, DNA was obtained from a small number of cells (20-400) isolated with a micropipette without setting up laboratory cultures (52 isolates), and phylogenetic analyses were based on the variation in nSSU rDNA. Apart from L. ovum and L. globulus, 13 other species were distinguished and four taxa (Lepocinclis conica comb. nov., L. fominii comb. nov., L. gracilicauda comb. nov., and L. pseudofominii nom. nov.) had their taxonomic ranks changed. For all verified species, diagnostic descriptions were emended and epitypes designated. The only exception was L. ovum, for which the epitype was questioned and thus, a new candidate for the epitype was suggested for future adoption.