Abstract
BACKGROUND: Indonesia holds immense biocultural diversity, yet ethnobotanical data remain fragmented. This systematic review synthesizes medicinal plant use across the archipelago to identify cross-cultural patterns, define a core ethnomedicinal flora, and critically appraise methodological rigor. METHODS: In adherence to PRISMA 2020 guidelines, primary field studies were retrieved from PubMed, Scopus, and GARUDA. Scientific names were harmonized using Plants of the World Online (POWO), and therapeutic indications were mapped to ICPC-2 disease categories. Methodological quality was assessed using a modified JBI checklist. RESULTS: A total of 91 studies were analyzed, yielding 3,202 use-reports for 791 medicinal plant species. Documentation was found to be geographically skewed toward Sumatra and Java, leaving Eastern Indonesia significantly underrepresented. A shared medicinal flora of 239 species was identified across multiple ethnic groups, dominated by versatile plants such as Zingiber officinale and Orthosiphon aristatus. High consensus was observed for acute conditions (e.g., Psidium guajava for diarrhoea), whereas chronic diseases like hypertension demonstrated diverse plant utilization. Quality assessment revealed that 89% of the included studies lacked explicit ethics reporting, and 32% relied on secondary identification without voucher specimens. CONCLUSIONS: A culturally salient core of medicinal plants was identified alongside unique regional adaptations. However, the existing literature is compromised by weak taxonomic validation and non-standardized reporting. Future research priorities must include the documentation of neglected regions and the enforcement of rigorous, voucher-based methodologies.