Figure 1.

Morphological traits of H. officinalis subsp. aristatus. (a) The stem is quadrangular and pale green; (b) Flowers grouped in axillary verticillaster, facing one side—calyx slightly reddened, pubescent, tubular, and with aristiform teeth—flower with bilobo upper lip—flower in which long protruding stamens can be seen; (c) leaves lanceolate, briefly petiolate—acute floral leaves, aristate at the apex; (d) ovoid or oblong tetrachene, with three obtuse edges, glabrous and with minute dimples (fruit).