Gibellula (Cordycipitaceae) includes widely distributed spider pathogenic fungi. This study describes a novel species, Gibellula agroflorestalis, recorded in agroforestry systems (AFS) and Atlantic Forest remnants in Pernambuco State, northeastern Brazil. The morphology of synnemata and conidiophores was studied, and phylogenetic analyses used SSU, LSU and TEF1 data in order to confirm the distinctiveness of the new species. The new species presents particular morphological characteristics, such as lacrimoid conidia and white synnemata. Comparison with other species in the genus revealed significant differences both in conidial and synnematal morphology. Based on Maximum Likelihood and Bayesian Inference phylogenies, G. agroflorestalis is a sister species to G. pulchra. The variations observed in the samples may be attributed to the microenvironmental conditions of AFS, which can influence phenotypic expression. This research emphasizes the importance of AFS in biodiversity conservation and in the discovery of new species.