Novel Hawksworthiomyces (Ophiostomatales, Ophiostomataceae) and Melnikomyces (Venturiales, Sympoventuriaceae) species and a new host record of Hawksworthiomyces on Lindera aggregata from China

During a survey of root-associated fungal diversity of the medicinal plant Lindera aggregata in Anhui Province, China, three noteworthy fungal taxa belonging to Hawksworthiomyces and Melnikomyces were identified. Morphological and multilocus phylogenetic analyses revealed two previously undescribed species and one new host record. Hawksworthiomyces rhizosphaerae sp. nov. and Melnikomyces linderae sp. nov. are hereby described as new to science, while H. taylorii is reported for the first time from the roots of L. aggregata.

Hawksworthiomyces rhizosphaerae is characterized by polyblastic conidiogenous cells bearing short cylindrical denticles and producing aseptate, hyaline, pyriform to ellipsoidal conidia, with secondary conidia frequently observed. Melnikomyces linderae is distinguished by pale brown to brown conidiophores, polyblastic conidiogenous cells with cylindrical denticles, verrucose 1 (– 2) - septate conidia released by rhexolytic secession, and globose to subglobose chlamydospores.

Detailed descriptions and illustrations of these taxa are provided. These findings expand the known diversity of Hawksworthiomyces and Melnikomyces and contribute to the understanding of the root-associated fungal communities of L. aggregata in China.