The Acacia senegal complex is formed by closely related species of Acacia senegal (L.) Willd. These species share several botanical characters, so from a morphological point of view, there is no clear discontinuity between some of them. A. dudgeoni Craib ex Holland is one species of the A. senegal complex that was formerly described as A. senegal ssp. senegalensis var. samoryana (A. Chev.) Rob. In order to differentiate Acacia senegal from A. dudge- oni, we analyzed a range of morphological traits such as tree height and diameter in natural stands, and, at the nursery stage, seedling height, number of branches, main root depth, biomass dry weight and leaf characteristics. Within addition, molecular poly- morphism analyses were conducted using 11 micro- satellite markers. Leaf characteristics and molecular markers appear to be the most effective tools to distinguish A. senegal from A. dudgeoni. These tools can improve our understanding of the relationshipbetween two species belonging to the same species complex