Discovery of three rare acremonium-like fungi in the rhizosphere of Gaultheria leucocarpa var. yunnanensis resolves the sister relationship between Paraneoaraneomyces and Subuliphorum (Clavicipitaceae, Hypocreales)

Rhizosphere soils represent an underexplored reservoir of fungal diversity. In this study, three rare acremonium-like fungi were isolated from the rhizosphere of Gaultheria leucocarpa var. yunnanensis in Guizhou, China. Using a polyphasic taxonomic approach that integrates morphological observations with six-locus phylogenetic analyses (ITS, SSU, LSU, tef - 1 α, rpb 1, and rpb 2), the isolates were determined to represent two novel species and one new habitat record.

Paraneoaraneomyces guizhouensis and Subuliphorum cylindrosporum are proposed as new species, while the rare species Subuliphorum camptosporum is reported from the plant rhizosphere for the first time. Phylogenetic analyses provide strong support for resolving Paraneoaraneomyces and Subuliphorum as distinct sister genera, a relationship that was previously unresolved. Together with Neoaraneomyces, these genera form a well-defined lineage within Clavicipitaceae.

This study expands the known diversity and ecological range of these rare genera, clarifies their phylogenetic placement within Clavicipitaceae, and highlights the importance of rhizosphere sampling in uncovering hidden fungal diversity.