Leaf architecture of threatened <Aquilaria cumingiana> (Decne.) Ridley and <Aquilaria malaccensis> Lam. (Thymelaeales: Thymelaeaceae) using morphometrics analysis

Due to a very limited number of scientific studies on the morphology of the very closely related threatened species, Aquilaria cumingiana and Aquilaria malaccensis, it is very challenging to identify them thoroughly. The leaf architecture was studied in A. cumingiana and A. malaccensis of the family Thymelaeaceae. Quantitative and descriptive methods were used to assess 21 leaf-traits of A. cumingiana and A. malaccensis. The study indicated that 10 leaf traits, such as base shape, apex shape, secondary vein spacing, tertiary vein angle category, tertiary vein angle to primary, quaternary vein, venation pattern, laminar shape, base angle, and apex angle, are important for identifying, and distinguishing the leaf architecture of A. cumingiana, and A. malaccensis. This study highlights the importance of leaf morphology and venation patterns in identifying and differentiating A. cumingiana and A. malaccensis.