The morphological variability of the leaves and fruits of many local multifunctional plant species is a topic of particular concern to African researchers, all the more so in view of the threat of extinction of certain plants that still exist in the natural environment. One such species found in the upland savannah agroecological zone of Adamaoua in Cameroon is Syzygium guineense var. macrocarpum (Engl.) F. White, an endemic species of Myrtaceae. The problem has arisen of which sub-variety to choose for domestication purposes. Ethnobotany, because it investigates the relationships between people and plants over time, can provide essential information on local knowledge and preferences. Our aims were also to identify, describe and determine morphological descriptors (qualitative and quantitative) and sub-varieties of the plant. For this purpose, we interviewed 218 men and women from nine different ethnic groups and selected 256 trees belonging to the plant's sub-varieties growing in 100 m x 100 m quadrats. followed A factorial design (8 x 4 x 8 x 3) was chosen for the experimental set-up: 8 x 4 for the experimental unit; 8 for the number of study sites; 4 for the number of sub-varieties; 3 for the number of repetitions (3 leaves and 3 fruits on each stem), with primary data analysis for the sites and secondary analysis for the sub-varieties. The morphological descriptors were assessed for 768 leaves and fruits. Criteria for differentiation by peasant families were based on observations (colour, shape, etc.) of the trees, leaves and fruits. The descriptors for tree accessibility to better light conditions, yield and vegetative growth could be used as references in attempts to domesticate the plant. Sub-varieties 1, 2 and 3 were highly significant, with a total ethnobotanical use value of more than 3 out of the 4 identified. Molecular studies of genomic DNA (from chloroplasts and ribosomes) will help to draw final conclusions as to the environmental or molecular origin of the variability observed in this plant in ...