Disentangling leaf morphology in Daustinia montana (Convolvulaceae)

Daustinia montana (Convolvulaceae) is the only species of the genus, and is notable for its wide leaf variability. To understand whether this plasticity is correlated with the distribution of the species, linear morphometric and leaf contour analyses were performed. Specimens from herbaria were photographed, and pre-established linear measurements were made. A multivariate analysis was then performed to test the strength of associations among morphological characteristics, climatic variables, and distribution of the species. Elliptic Fourier analysis based on 20 harmonics was used to generate shape descriptors, resulting in nine main components. With elliptic Fourier descriptors, a grouping tree was created that suggests the existence of six morphotypes in D. montana. Moreover, clustering analysis revealed two large groups distinguished mainly by leaf width. The present findings indicate that the morphotypes are strongly related to latitude and that other characteristics such as the type of indumentum are related to climatic variables.