Molecular phylogenetics
Jaapia is a genus in the monotypic family Jaapiaceae and order Jaapiales. The order was first described in 2010. "Jaapia" is a genus of resupinate species that were until then classified in the order Boletales. Molecular phylogenetics analysis showed it to be a sister group (one of two clades resulting from the splitting of a single lineage) to the rest of the Agaricomycetidae.