Population, expanded distribution, and conservation of the Sumatran endemic tree Magnolia sumatrae (Dandy) Figlar & Noot.

Data deficiency remains a major constraint in understanding the extinction risk and conservation of Magnolia species globally. Magnolia sumatrae (Dandy) Figlar & Noot. is one of the Indonesian Magnolia species assessed as Data Deficient by the IUCN Red List. It is a tree endemic to Sumatra Island and is known only from Mount Singgalang, Mount Talamau, and Gunung Leuser National Park. In the present study, population surveys of M. sumatrae were conducted in the previously known locations. Additionally, new records of the species in Aceh Tengah Regency, Aceh Province, are reported, which represent its northernmost distribution on Sumatra Island. The implications of these new records for the conservation status of the species are discussed. To ensure the future survival of M. sumatrae , plant materials of the species have been collected to serve as ex situ collections for the first time and become the 11 th Magnolia native to the country available in the Indonesian ex situ collections. Using species distribution modeling methods, the potential distribution of the species is also presented, which predicts the potential habitat in Sumatera Utara Province, where no records have been available so far.