Molecular phylogeny and morphology reveal two novel entomopathogenic species of Hypocreales (Polycephalomycetaceae and Cordycipitaceae), from China

Based on an integrated taxonomic approach combining multi-locus phylogenetic analysis and morphological characterization, we formally describe and illustrate two new entomopathogenic fungal species from China, <i>Pleurocordyceps longiphialis</i> and <i>Samsoniella aggestitenuipes</i>. Phylogenetic analyses of a six-locus dataset (ITS, nr SSU, nr LSU, <i>tef1-α</i>, <i>rpb1</i>, and <i>rpb2</i>) strongly support the distinct phylogenetic positions of the two new species within their respective genera. Morphologically, <i>P. longiphialis</i>, isolated from a Scarabaeoidea larva, possesses notably elongated α-phialides (9.5-101 µm) and dimorphic conidia. In addition, <i>S. aggestitenuipes</i>, obtained from a lepidopteran pupa, displays synnemata with powdery conidial masses and phialides measuring 6-28 µm. This study also reviews the host ranges and geographic distributions of <i>Pleurocordyceps</i> and <i>Samsoniella</i>. <i>Pleurocordyceps</i> species are known to infect insects in Coleoptera, Hemiptera, and Lepidoptera, and also parasitize fungi such as <i>Elaphomyces</i>, <i>Ophiocordyceps</i>, <i>Paraisaria</i>, and <i>Perennicordyceps</i>. <i>Samsoniella</i> species have been reported from Lepidoptera, Coleoptera, Hymenoptera, and Arachnida. Geographically, <i>Pleurocordyceps</i> occurs in Asia (China, Japan, and Thailand) and South America (Ecuador), while <i>Samsoniella</i> is distributed across East Asia (China, Laos, Thailand, and Vietnam), Europe (UK and Ireland), and South America (Argentina).