Morfologia das cipselas, brácteas e folhas de Cololobus H. Rob. (Asteraceae)

Abstract

Anatomical and morphological studies contribute significantly to understanding the characteristics of taxa in Asteraceae. Inserted in the tribe Vernonieae, Cololobus is a genus of five species, whose understanding of its anatomical and morphological characteristics can contribute to the circumscription of the genus within the tribe. This work seeks to describe the characteristics present in the cypselas, bracts and leaves of all species of Cololobus, seeking common and distinct characteristics for the genus and for Vernonieae. For this, data obtained in anatomy and micromorphology. confirmed that the pattern of the pericarp, leaf mesophyll and bract mesophyll follow that described for other species of Vernonieae. In addition, some characters, such as the presence of branched trichomes on the bracts, are observed only in Cololobus species. Characteristics observed in this work, such as number of ribs, mesophyll pattern in leaves and bracts and arrangement of stomata of leaves and bracts are useful to distinguish Cololobus species from each other.