Functional groups in Lychnophorinae (Asteraceae: Vernonieae) based on morphological and anatomical traits

The Lychnophorinae subtribe (Asteraceae: Vernonieae) occurs mainly on the Central Brazilian Plateau, especially in areas characterised by intense solar radiation, large daily temperature fluctuations, water scarcity during autumn and winter, and frequent fire. However, a few species of Lychnophorinae, such as Blanchetia heterotricha DC., are not restricted to the Cerrado Domain, but can live in open and humid areas of borders of the Atlantic Forest. To understand the mechanisms of Lychnophorinae adaptation to these environmental conditions, habit, leaf and stem functional traits from 12 species were analysed. Leaf and stem samples were processed and stained using standard plant-anatomy methodology. A comparative analysis of functional groups was performed by principal coordinates analysis, which was applied to two matrices of 30 qualitative and five quantitative traits. The multivariate analysis based on qualitative traits highlighted the following four functional types that might be linked to ecological conditions: Group I adapted at open and humid areas of borders of the Atlantic Forest; Group II, with features mostly related to foggy habitats; Group III, exhibiting traits quite adapted to the seasonally dry and variable conditions of the campos rupestres; and Group IV, showing the most specialised morphological and anatomical traits, which might be related to the extreme conditions of the campos rupestres.