A new remarkable Vanilla Mill. (Orchidaceae) species endemic to the Espinhaço Range, Brazil: its phylogenetic position and evolutionary relationships among Neotropical congeners.

Abstract

During surveys conducted on Neotropical Vanilla, a new endemic species was found in the Brazilian campos rupestres of the Espinhaço Range. Here, this new remarkable Vanilla species, namely V.rupicola Pansarin & E.L.F. Menezes, is described and illustrated. A phylogeny for Vanilla is presented and the relationships between Neotropical species are discussed. The position of V.rupicola among Neotropical Vanilla is discussed within an evolutionary context. Vanillarupicola is recognized by its rupicolous habit, its reptant stems, and its sessile and rounded leaves. This remarkable new taxon emerges in a clade that includes V.appendiculata Rolfe and V.hartii Rolfe. Vegetative and floral features support a close relationship between V.rupicola and sister taxa, mainly regarding the apical inflorescence (V.appendiculata), the type of appendages of the central crest of the labellum, and the labellar color pattern. Phylogenetic inference suggests that the circumscription of Neotropical Vanilla groups needs revision.