A taxonomic study of two Stichococcus species (Trebouxiophyceae, Chlorophyta) with a starch-enveloped pyrenoid
Neustupa, Jiří; Eliáš, Marek Š ejnohová
We investigated the morphology, ultrastructure and 18S rDNA molecular phylogeny of a green algal strain previously described as Klebsormidium marinum and a similar new strain isolated from Southeast Asia. Ultrastructural features and molecular phylogenetic analyses revealed that the two strains are unrelated to the charophycean genus Klebsormidium and belong to the trebouxiophycean genus Stichococcus, despite the presence of a pyrenoid with a conspicuous starch envelope. The two strains are indistinguishable at the ultrastructural level, but only one strain forms filaments of 4-10 cells on solid medium. The 18S rDNA sequences indicate that the strains represent separate species. We propose the two strains be classified as Stichococcus deasonii nomen novum and Stichococcus jenerensis species nova, respectively.