Leaf epidermal features as taxonomic characters in some Lannea spieces (Anacardiaceae) from Nigeria.

Leaf epidermal morphology of seven species of Lannea in the family Anacardiaceae were studied, namely: L. kerstingii, L. welwitschii, L. schimperii, L. egregia, L. acida, L. microcarpa, and L. fruticosa. The study revealed that several interesting characters, such as anticlinal cell wall pattern (ACWP), epidermal cell wall shape (ECWS), epidermal cell size (ECS), stomatal complex type (SCT), stomatal density (SD), stomatal size (SS), stomatal index (SI), and trichomes are constant and variable within and between some genera. ACWPs are straight, curved, round and undulate in the studied species. ECWS are found to be polygonal on both leaf surfaces, except in L. fruticosa. Stomata occur only on the abaxial leaf surface in all studied species; cyclocytic and anomocytic stomatal complex types are the only two types found, the anomocytic type occurring in five species: Lannea kerstingii, L. welwitschii, L. schimperii, L. egregia, and L. acida. Stomata are smaller in size in all species. Another important fact is that SD and SI vary from species to species. Out of the seven Lannea species, only three possess trichomes, namely L. kerstingii, L. schimperii and L. fruticosa. Thus the abovementioned leaf features are of great taxonomic significance. [ABSTRACT FROM AUTHOR]