Two New Species of Viburnum (Viburnaceae) from the Tropical Andes
Viburnum obtectum H. Vargas and V. stipitatum H. Vargas are described as new species. They differ from all other Ecuadorian species of Viburnum L. by having marginal teeth along the whole margin of the leaves, while such teeth are in other species restricted to either the basal or apical half of the leaf. Differences between the two new species are expressed particularly on the abaxial leaf surface. Viburnum obtectum is extremely densely pubescent; the indument completely obscures the abaxial leaf surface, and the stellate trichomes are almost always sessile. Viburnum stipitatum has a visible abaxial leaf surface, with long-stalked stellate trichomes having a forest-like appearance. A key to the Viburnum species in Ecuador is provided, as well as illustrations of the new proposed species.