Leaf morphological variation in common yew (Taxus baccata L.) at the species’ southern range margin in North Africa

The main aim of this study was to provide the first morphometric characterization of  Taxus baccata  L. leaves in North Africa. Phenotypic variability was investigated in nine natural populations from Algeria and Morocco using 11 quantitative and qualitative traits. analysis  of variance (ANOVA) followed by Fisher’s post hoc test revealed significant differences at multiple hierarchical levels, including trees within populations, among populations, regions and mountain ranges for all quantitative variables. In parallel chi-square analysis indicated significant variation in qualitative traits. Hierarchical clustering classified the studied populations into two major clusters for both types of morphological traits. The Chrea population displayed the largest leaves, whereas the Saharan Atlas populations showed the smallest. Principal component analysis (PCA) clearly separated populations and geographic groups in relation to both ecological and leaf morphological factors. Overall, the observed morphological differentiation suggested that phenotypic plasticity together with possible genetic differentiation, is driven more by local ecological conditions than by latitude alone. North African yews are characterized by relatively  narow leaves and region specific variation in petiole and apex morphology, reflecting high degree of ecological adaptability to various ecological and geographical conditions. These findings have important implications for conservation of southern marginal population of this relic threatened conifer. Article history: Received 8 January 2026; Revised 29 April 2026; Accepted 16 June 2026; Available online 25 June 2026.