Gibellula aurea sp. nov. (Ascomycota, Cordycipitaceae): a new golden spider-devouring fungus from a Brazilian Atlantic Rainforest

Abstract

Fungal parasites that infect spiders can affect their survival and potentially their behaviour. The genus Gibellula (Ascomycota, Cordycipitaceae) infects arachnids, and due to difficulties in identifying hosts after fungal sporulation, its ecology and spider host diversity are poorly understood. Herein, we propose a new species of Gibellula from the Brazilian Atlantic Forest: Gibellula aurea, which parasitizes two spider families (Anyphaenidae and Corinnidae). Gibellula aurea exhibits characteristic golden-yellow hyphae that completely cover hosts and white conidiophores emerging along synnemata or directly from hosts. Molecular identification was performed by sequencing the small and large nuclear ribosomal subunits, translation elongation factor, and RNA polymerase II second largest subunit regions, and reconstructing multigene phylogenetic trees. Maximum Likelihood and Bayesian Inference phylogenies demonstrate that G. aurea forms a well-supported clade closer to G. flava, G. gamsii, G. leiopus, G. longispora, G. pigmentosinum, and G. pulchra. The phylogenetic reconstruction displayed herein represents the most comprehensive phylogeny for this genus to date. Spider hosts parasitized by G. aurea have been invariably found attached underneath leaves in vegetation, regardless of the identity of the infected hosts. The consistency of the death locations of G. aurea hosts indicates recurrent behaviour given the habitat heterogeneity of these host groups. Nevertheless, it is still unclear to what extent the place where hosts die can favour parasite fitness.