Ethnobotanical study of traditional medicinal plants used by the Sidama people to treat human ailments in the Bensa district of Sidama region, Ethiopia

• The Sidama people possess a diversity of medicinal plants and traditional knowledge related to their use. • A total of 214 species of medicinal plants belonging to 80 families and 182 genera were recorded. • Acanthus senni, Bothriocline schimperi, Rosa abyssinica, Rhus glutinosa, and Vepris dainellii are novel uses of endemic medicinal plants in the study area. • The culture-based management of sacred forests would help safeguard medicinal plants in the district. : Traditional medicinal plants are integral to Ethiopia's primary healthcare system. The Sidama people have a profound spiritual connection to sacred forests and traditional medicines. However, despite preserving a diverse range of indigenous traditional medicinal plants, the traditional knowledge in treating human ailments in the Bensa district has not yet been ethnobotanically explored. This study aims to document and analyze the use of medicinal plants in managing human ailments and the associated knowledge used by the Sidama people of the Bensa district. : The ethnobotanical data was collected from 84 informants through semi-structured interviews and group discussions and 90 informants through focus group discussions. The data were analyzed using descriptive statistics, use reports (UR), informant consensus factor (IFC), and fidelity level (FL). Medicinal plant specimens were collected and deposited at the herbarium of the Ethiopia Biodiversity Institute and Shashemene Botanical Garden. : A total of 214 species of medicinal plants belonging to 80 families and 182 genera were documented. Asteraceae and Lamiaceae contribute the highest number of species. Leucas martinicensis (Jacq.) R. Br. (UR, 41), Bersama abyssinica Fresen. (UR, 40), and Asparagus africanus Lam (UR, 38) were the most popular species used by local people, with the highest healing potential of medicinal plants. The cancer disease category had the highest consensus value (0.90), and two species, Zanthoxylum chalybeum Engl and Asparagus africanus , were identified as most effective in treating cancer-related ailments. The study also revealed novel uses of certain endemic medicinal plants such as Acanthus senni Chiov, Bothriocline schimperi Oliv. & Hiern ex Benth, Rosa abyssinica Hochst, Rhus glutinosa . ex A. Rich., and Vepris dainellii (Pic.Serm.) Kokwaro in managing specific ailments for the first time. : The Sidama people have a rich history of preparation and application of diverse plants for ethnomedicinal purposes. However, the existence of ethnomedicinal resources is threatened by agricultural expansion, urbanization, and firewood collection. Therefore, in-situ and ex-situ conservation of medicinal plants are crucial for their future utilization. In addition, more substantial formal support for the existing culture-based protection and management of sacred forests is required to safeguard medicinal plants in the Sidama region. The medicinal efficacy of the studied plants raises awareness of the conservation of valuable plants implicated in treating diverse ailments.