Tremella ananatis sp. nov. and Tremella lamprococci sp. nov., two yeast species associated with bromeliads.

Eight yeast isolates with an affinity to the genus Tremella were obtained from bromeliads from different locations in Brazil. Although the formation of basidia and basidiocarp were not observed, on the basis of the results of sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) region, we suggest that these isolates represent two novel species of the genus Tremella. These yeasts are phylogenetically related to Tremella saccharicola and Tremella globispora. Therefore, we propose Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. as novel yeast species of the order Tremellales (Agaricomycotina, Basidiomycota). Sequence analysis revealed that Tremella ananatis sp. nov. differs by 11 and 28 nucleotide substitutions from Tremella saccharicola in the D1/D2 sequence and ITS region, respectively. Moreover, Tremella lamprococci sp. nov. differs by 15 and 29 nucleotide substitutions from Tremella globispora in the D1/D2 sequence and ITS region, respectively. The holotypes of Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. are CBS 14568T and CBS 14567T, and the MycoBank numbers are MB840480 and MB840481, respectively.

Yeast in plant phytotelmata: Is there a "core" community in different localities of rupestrian savannas of Brazil?

Ephemeral microbial communities usually undergo priority effect and result in higher diversity with a few representatives of each species. Community structure of yeasts in bromeliad tanks was compared between two rupestrian savanna (Cerrado) areas in Brazil and to yeasts isolated from water holes in the same areas. Water samples were collected from 60 tanks of bromeliads Bromelia karatas and Encholirium sp. and rock holes at the Karstic Area of Aurora, Tocantins State and 60 tanks of Vriesea minarum (Bromeliaceae) and Paepalanthus bromelioides (Eriocaulaceae) at Serra do Cipó National Park, Minas Gerais State in Brazil. The yeast diversity comprised 90 species from which 60% are basidiomycetous yeasts usually associated with phylloplane, soils, and aquatic habitats. The species Papiliotrema laurentii, Rhodotorula mucilaginosa, Pa. nemorosus, and Pseudozyma hubeiensis were the most frequent species associated with bromeliads. Eighteen yeast species, two ascomycetous and 16 basidiomycetous, were consistently isolated from the substrates in both areas and may represent a core community in bromeliads in rupestrian fields. Singlets occurred in 38 to 69% of samples, and 32 species were isolated only once. Our findings reinforce the ephemeral nature of the yeast communities associated with tank-forming plants in which individual phytotelmata act as patches or aquatic islands prone to rapid colonization-extinction rates receiving inocula from plant and soil debris. Ephemeral rock holes also represent a transitory habitat for yeast species associated with plants and soil.