Background: It has been suggested that niche differentiation could explain species coexistence in hyper-diverse tropical plant communities. Questions: Can we identif y a specific and differentiated leafchemical variation ofseven coexisting legume species within the hyper-diverse tropical semi-desert? Are these differences related to their phylogeny? Studied species: Vachellia constricta, Parkinsonia praecox, Mimosa luisana, Neltuma laevigata, Vachellia campechiana, Vachellia bilimekii, and Senna wislizeni. Study site and date: Zapotitl & aacute;n Salinas Valley in Mexico (August 2020). Methods: For each species we assessed nine foliar elements (hydrogen , carbon, nitrogen , phosphorus , calcium, magnesium, potassium, iron , and zinc). We constructed a phylogenetic tree from sequences of the GenBank database selecting the marker trnL chloroplast intron. Differences were assessed performing ANOVA , Principal Component Analysis and Spearman's multiple correlation analyses. Results: Leaf chemical variation exhibited greater differentiation in phosphorus (associated to nucleic acids , protein construction and rapid growth rate) , calcium and potassium (associated to structure and photosynthesis) , and iron and zinc (associated to enzymes). Leaf chemical variation of more ancestral species displayed elevated concentrations of calcium and potassium , whereas most derived species exhibited higher carbon and iron concentrations. Species of the same genus showed less differences compared to more distant species. Conclusions: The foliar elemental composition may be a fingerprint trait ofthe ecological and evolutionary history ofthese legumes, in relation to nutrient assimilation and acquisition, and probably constitute a mechanism of coexistence.