Abstract: Leaf epidermis of 31 species belonging to 12 genera of the tribe Mutisieae from both East Asia and South America was investigated by light microscopy (LM) and scanning electron microscopy (SEM). It was shown that the stomatal apparatus was mainly staurocytic and anomocytic, and presented in abaxial epiderimis of all studied species and in the adaxial epidermis of some species. The leaf epidermal cells were usually polygonal or irregular bearing with the anticlinal walls straight or arched, sinuolate, sinuous to sinuate. The major shapes of stomatal apparatus were elliptical or nearly rounded, the inner margin of the outer stomatal rim ranged from nearly-smooth to sinuolate, the outer stomatal rim of Macroclinidium was two pairs and quite different from other species. The leaf surface is mostly smooth and no waxy or corneous types; however there are some species with the surface covered with ridges of wax or waxy types. The result showed that the characters of leaf epidermis were little difference among species but can serve as a criterion for distinguishing among genera, in particular among generic groups and subtribs.

Key words: Leaf epidermis