New flower‑associated yeasts discovered in northern Thailand

In a recent study published by MycoKeys, researchers Chirayut Kathongthung, Pratthana Kodchasee, Saowaluck Singsalood, Chanokned Senwanna, Pannida Khunnamwong, Jaturong Kumla, and Nakarin Suwannarach isolated two novel species of Papiliotrema (Rhynchogastremataceae) from flowers collected in Chiang Mai Province, northern Thailand, in 2024.¹.net]

The team sampled five flowering plants—Allamanda cathartica, Bidens pilosa, Cananga odorata, an unidentified Oncidium orchid, and Plumeria obtusa—and isolated six distinct strains of Papiliotrema. Using an integrative taxonomic approach that combined multilocus phylogenetic analyses with detailed phenotypic characterization, they identified two new species: P. anthoicola sp. nov., holotype SDBR‑CMU883T, and P. floralis sp. nov., holotype SDBR‑CMU888T.¹.net]

Phylogenetically, the authors used sequences from the internal transcribed spacer (ITS), the D1/D2 domains of the nuclear ribosomal large subunit (D1/D2), the largest subunit of RNA polymerase II (rpb1), the second-largest subunit of RNA polymerase II (rpb2), and translation elongation factor 1-alpha (tef1-α). This placed the two taxa within the broader Papiliotrema clade while distinguishing them from closely related species.¹.net]

Morphologically, both species showed typical yeast traits but differed in colony texture and microscopic features such as cell size and budding patterns. Growth tests on selective media and temperature tolerance assays confirmed their distinctiveness at the species level.¹.net]

The discovery has implications beyond taxonomy. Yeasts like those found here are often present on flower surfaces or interiors, facilitating nutrient acquisition and influencing pollination dynamics. This expands our knowledge of plant–fungi symbioses and ecological networks in tropical ecosystems.

For mushroom foragers, understanding these fungal communities can inform habitat assessments and conservation priorities, especially where rare or endangered flora coexist with specialized microorganisms. While they are not known to be edible, the new species highlight complex microhabitats that support diverse mycelial life forms in Thailand’s rich botanical landscapes.

Overall, the Chiang Mai study adds two novel members to the Papiliotrema genus, underscores the importance of integrating molecular data with phenotypic analysis, and points toward broader ecological roles of yeasts within flowering plants across Southeast Asia.¹.net]