Multi-gene phylogeny and morphology of Pleurotus in Aotearoa New Zealand reveal a new variety of Pleurotus pulmonarius

Increased demand for cultivated oyster mushrooms ( Pleurotus species) in Aotearoa New Zealand has led to the importation of exotic species, which pose potential invasion risks. Gaps in taxonomic knowledge of this genus have complicated biosecurity decisions and cultivation efforts. To address this, we collected 84 wild and cultivated New Zealand Pleurotus specimens for multi-locus phylogenetic analysis (ITS, LSU, RPB1, RPB2, and Tef) and morphological examination. We describe P. pulmonarius var . aotearoa as a new variety indigenous to New Zealand, distinct from imported P. pulmonarius sens . str. We establish that P. purpureo-olivaceus has no anamorphic stage and falls outside the subgenus Coremiopleurotus , unlike P. australis, a species sometimes found on living trees. The close monophyletic relationship between P. parsonsiae and P. djamor underscores the need to reconsider the presence of the exotic P. djamor in the country. The refined species boundaries between the indigenous P. australis, P. parsonsiae, P. pulmonarius var . aotearoa and P. purpureo-olivaceus have important implications for conservation and biosecurity, and support the potential of using indigenous strains for cultivation in New Zealand. • Multi-gene phylogeny resolves four indigenous Pleurotus species in New Zealand • P. pulmonarius var. aotearoa is described as a new indigenous variety • ITS alone is insufficient to delimit closely related Pleurotus lineages • Imported P. djamor and P. pulmonarius are genetically distinct from indigenous species • Taxonomic misidentification led to import approval of potentially invasive species