- Volume 63, Issue Pt_1, 2013

During an investigation of olive oil microbiota, three yeast strains were found to be divergent from currently classified yeast species according to the sequences of the D1/D2 domain of the gene encoding the rRNA large subunit (LSU) and the internal transcribed spacer region including the gene for 5.8S rRNA. Phylogenetic analysis revealed that these strains, designated CBS 12509, CBS 12510T and CBS 12511, represent a novel anascosporogenous species described herein as Yamadazyma terventina sp. nov; the type strain is DAPES 1924T ( = CBS 12510T = NCAIM Y.02028T). This novel species was placed in the Yamadazyma clade, with Yamadazyma scolyti, Candida conglobata and Candida aaseri as closest relatives. Y. terventina differs from the above-mentioned species in the ability to strongly assimilate dl-lactate and weakly assimilate ethanol.

The diversity of green microalgae in subaerial habitats remains largely unexplored and a number of new genus- and species-level lineages have been discovered recently. The traditional green algal genus, Chlorella, which accommodated coccoid unicellular green algal species with globular to oval cells, reproducing entirely by autospores, has been found to be polyphyletic. In this study, we provide a detailed characterization of two strains of microalgae isolated from tree bark in the Mediterranean. These algae share the general Chlorella-like morphology and their 18S rRNA and rbcL gene sequences place them in the Trebouxiophyceae. Strain CAUP H8401 forms an independent trebouxiophycean lineage, together with three previously published 18S rRNA gene environmental sequences of undescribed microalgae, which were retrieved from profoundly different habitats. In contrast, strain CAUP H7902 is related to Kalinella bambusicola in the Watanabea clade of the Trebouxiophyceae on the basis of its 18S rRNA gene sequence. This relationship is also supported by the rbcL gene sequence, acquired from the type strain of K. bambusicola. The investigated strains are described as representatives of a novel species in a new genus, Leptochlorella corticola gen. et sp. nov., and a novel species, Kalinella apyrenoidosa sp. nov., according to the International Code of Nomenclature for Algae, Fungi and Plants.

Five yeast strains (Ym24403, Ym24404, Ym24408, Ym24409 and Ym24410T) were isolated from different flowers of Erianthus rufipilus (Gramineae), a wild plant growing in the phosphorus-rich region in Yunnan Province, south-western China, and were found to be phenotypically and genetically divergent from currently recognized yeast species. Sequence analysis of the D1/D2 domain of the large subunit rRNA gene revealed that the five strains represented a novel species described as Starmerella jinningensis sp. nov. The type strain is Ym24410T ( = CBS 11864T  = CCTCC AY 2011002T). Phylogenetic analysis based on the D1/D2 region of the large subunit rRNA gene suggested that S. jinningensis sp. nov. is placed within the Starmerella clade.

In the course of an on-going study aimed at cataloguing the natural yeast biodiversity found in Ecuador, two strains (CLQCA 13-025 and CLQCA 20-004T) were isolated from samples of cow manure and rotten wood collected in two separate provinces of the country (Orellana and Bolívar). These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to belong to the Metschnikowia clade and to be most closely related to Candida suratensis, a species recently discovered in a mangrove forest in Thailand. The species name of Candida ecuadorensis sp. nov. is proposed to accommodate these strains, with strain CLQCA 20-004T ( = CBS 12653T = NCYC 3782T) designated as the type strain.