Citrus halimii
Like other papedas, the halimii has relatively large leaves, with a long, winged petiole.The yellow-green segments are filled with a number of large seeds, and a small quantity of juice.[2] Historically, limited characterization made appropriate taxonomic placement of the mountain citron unclear, with particular uncertainty over whether it was a natural hybrid or a pure wild species.A 2022 study of the genomics of the mountain papeda revealed it to have low levels of heterozygosity, consistent with it being a true citrus species and not a hybrid variety.Its genetic markers, along with the profile of its essential oils, showed it to be most closely related to kumquats.