An integrative taxonomy approach reveals Saccharomyces chiloensis sp. nov. as a newly discovered species from Coastal Patagonia

• DOI: 10.1371/journal.pgen.1011396
• Publication Date: 2024-09-06T18:26:35Z
• Authors: Tomas A. Peña; Pablo Villarreal; Nicolas Agier; Matteo De Chiara; Tomas Barría; Kamila Urbina; Carlos A. Villarroel; Ana R. O. Santos; Carlos A. Rosa; Roberto F. Nespolo; Gianni Liti; Gilles Fischer; Francisco A. Cubi...
• Keywords: Reproductive isolation; Lineage (genetic)

Species delineation in microorganisms is challenging due to the limited markers available for accurate species assignment. Here, we applied an integrative taxonomy approach, combining extensive sampling, whole-genome sequence-based classification, phenotypic profiling, and assessment of interspecific reproductive isolation. Our work reveals presence a distinct Saccharomyces lineage Nothofagus forests coastal Patagonia. This lineage, designated chiloensis sp. nov., exhibits 7% genetic divergence from its sister S . uvarum , as revealed by sequencing population analyses. The South America-C (SA-C) Patagonia forms unique clade closely related previously described divergent Oceania (AUS, found Australia New Zealand). reclassification supported low Ortho Average Nucleotide Identity (OANI) 93% SA-C AUS relative which falls below suggested threshold 95%, indicating independent evolutionary lineage. Hybrid spore viability provided compelling evidence that are reproductively isolated In addition, structural variants between nov. lineages, including large-scale chromosomal translocations inversions, together with profile, emphasizing their intraspecies distinctiveness. We suggest nov diverged allopatry glaciation, followed post-glacial dispersal, resulting lineages on opposite sides Pacific Ocean. discovery illustrates uniqueness Patagonia’s biodiversity underscores importance adopting taxonomic approach unveil cryptic microbial species. holotype CBS 18620 T