Botryoconidia X. Yu. Zhang, Q. Y. Zhang & B. Fan gen. nov.

Etymology.

Derived from the Latin words “botrys” and “conidium”, referring to the grape-like clustered arrangement of conidia.

Type species.

Botryoconidia globosus X. Yu. Zhang, Q. Y. Zhang & B. Fan, sp. nov.

Description.

Colonies olive, tomentose, with irregularly margins. Hyphae hyaline to pale brown, smooth to verruculose, septate, branched, varying in shape from straight to wavy or curved. Asexual state: Conidiophores reduced to conidiogenous cells or occasionally absent. Conidiogenous cells integrated, terminal or intercalary, hyaline to pale brown, smooth-walled, arising from vegetative hyphae, producing conidia either synchronously or successively. The apex of the conidiogenous cells often slightly swollen or constricted after conidium secession. Conidia developing directly on hyphae in an apical or lateral manner or on conidiophores, suboval to elliptical, smooth, occasionally aggregated in clusters. Sexual state not observed.

Notes.

Extremaceae was introduced by Quaedvlieg et al. (2014) and has since been expanded to include ten genera, reflecting growing research interest in this family. Most of the species in Extremaceae are rock-inhabiting taxa, saprobes, or isolated from soil. In this study, however, the genus Botryoconidia, represented by an endophytic strain from Pinus densiflora, forms a distinct lineage within Extremaceae (Fig. 4). Morphologically, Botryoconidia differs significantly from other genera in this family. While conidia in other Extremaceae genera are typically solitary or arranged in chains (Videira et al. 2017), those of Botryoconidia are oval-granular and aggregated in grape-like clusters.