Anatomia foliar comparada de Vellozia Vand. (Velloziaceae)

Abstract

Vellozia Vand., popularly known as canela-de-ema, is the largest genus of Velloziaceae, with 125 species, 123 of which are endemic to Brazil. Anatomically, Vellozia species present the organization of tissues that allow them to survive in adverse environments, with poor soils, low water availability and the occurrence of fire, and may also represent important diagnostic characters. When compared with exsicata specimens of Vellozia barbaceniifolia Seurb., the individuals collected in Serra do Pires presented a set of distinct characters that are relevant to the taxonomy of the genus. The new species is proposed, so far, based on consistent morphological characters that distinguish it from Vellozia barbaceniifolia, including larger dimensions of the leaves, pedicel and capsule, a hypanthium without angles (rounded, in contrast to the clearly tricarenate hypanthium of V. barbaceniifolia) and a number of stamens greater than 30, while in V. barbaceniifolia the number of stamens is invariably 30. In order to contribute with morphological data for the separation and identification of a new species of Vellozia, the present work was proposed. This study presents the anatomical characterization of the leaf blades and sheath of Vellozia sp. and the leaf blade of V. barbaceniifolia, comparing the leaf characterization of both species. The anatomical pattern of the genus was observed in both species; however, differences in the distribution pattern and size of epidermal cells in paradermal view, as well as in the shape of the emergences located on the margin and abaxial face of the main vein and in the papillose cells present in the grooves of the stomatal crypts, contribute to the separation between the specimens of these two species. Furthermore, the anatomical characterization of the sheath represents an important contribution to the genus and the Velloziaceae family, due to the scarcity of studies on this structure.