Morphology and multigene phylogeny reveal three new species of Samsoniella (Cordycipitaceae, Hypocreales) from spiders in China.

ABSTRACT

The genus Samsoniella was erected based on orange cylindrical to clavate stromata, superficial perithecia and conidiophores with Isaria-like phialides and to segregate them from the Akanthomyces group. In this study, based on morphological features and multigene (SSU, LSU, TEF, RPB1 and RPB2) phylogenetic analysis six Samsoniella species parasitizing spiders were collected in China. Three of them belong to known species S.alpina, S.erucae and S.hepiali. Three new species S.anhuiensissp. nov., S.araneasp. nov. and S.fusiformisporasp. nov. are illustrated and described. They are clearly distinct from other species in Samsoniella occurring in independent subclades. Furthermore, among the four insect-pathogenic fungi specimens collected from similar sites, three of them were identified as the new species described below. Our study significantly broadens the host range of Samsoniella from Insecta to Arachnida, marking a noteworthy expansion in understanding the ecological associations of these fungi. Additionally, the identification of both mononematous and synnematous conidiophores in our study not only expands the knowledge of Samsoniella species but also provides a basis for future research by comparing the ecological significance between these conidiophore types. In conclusion, our study enhances the understanding of Samsoniella diversity, presenting a refined phylogenetic framework and shedding light on the ecological roles of these fungi in spider parasitism.