Morphological diversity and evolution of the ligule and the contraligule in Scleria and related genera

Abstract

Cyperaceae is the second largest family of Poales, with about 5700 species distributed in two subfamilies and 95 genera. This family is characterized by the 3-sided stem, the characteristic spike-shaped inflorescence, and the absence of ligule. However, some genera differ from this last characteristic, for example, Fuirena Rottb., Carex L. and Scleria P.J.Bergius. Scleria is the sixth largest genus of the family, with species where the ligule and the contraligule is present. Such structures are useful in the taxonomy of the genus, allowing the characterization of species and being commonly present in identification keys. In order to understand the morphological diversity, exsiccatae from one international herbarium will be observed. It will be registered the morphological characters of the two structures and the exsiccatae analyzed will be photographed for posterior comparison. The data will be condensed in a character matrix and conflicted with the literature. After, ancestral characters estimations will be made, in order to understand the evolution of the two structures. The information obtained will be very useful to clarify several aspects concerning the morphological diversity of the ligule and contraligule in Scleria. (AU)