Botanical novelties from Sierra de Maigualida, southern Venezuela. I

Abstract

The almost unexplored Sierra de Maigualida is the largest and highest non sedimentary, granitic mountain system in the Guayana Shield. Because of its particular geological constitution, a surprisingly large number of new plant taxa has been found in its high mountain ecosystems. In this first installment, two new species, Sauvagesia cryptothallis (Ochnaceae) and Aegiphila uasadiana (Lamiaceae) are described and illustrated. Sauvagesia cryptothallis belongs to Sauvagesia sect. Imthurnianae and is closely related to S. imthurniana, differing mainly in the axis of the inflorescence being densely covered by 5-8 tightly overlapping bracts, hiding the entire axis, and with the principal and secondary leaf veins almost flat, not salient on the lower surface, and poorly differentiated from tertiary veins. Aegiphila uasadiana is a very distinctive species somewhat similar to A. luschnathii, from Brazil. It can be distinguished by its leaves that are coriaceous, conspicuously revolute, entire, shiny, gla brescent, conspicuously bullate, and foveate adaxially; the inflorescences that are relatively compact and crowned at the apex of the twigs; the calices that are adpressed-pubescent, densely so at the base, progressively glabrescent towards the apex, truncate apex, 4-apiculate, each apiculi of ca. 0.4 mm long, and stamens that are largely exserted from the corolla.