Capsule structure in three species ofDyckia(Bromeliaceae): Ontogenetic and taxonomic issues1

Abstract

Dyckia is characterized by conserved external floral and fruit morphology. Considering the conservative morphology of Dyckia fruits, anatomical features could be an important source of phylogenetically useful characters. The objectives of this study were to characterize fruit ontogeny and dehiscence in three species of Dyckia (Dyckia distachya, Dyckia reitzii, and Dyckia remotiflora), and in the process to identify characters that contribute to the systematics of the genus and family. Differences were found among species in the number of mesophyll/mesocarp layers, presence of pluristratified hypodermis, presence of mucilage secretory structures, and presence of perivascular bundle sheath extensions. In addition, a xerochastic mechanism of dehiscence in Dyckia denticidal capsules is described here for the first time. As a potential source of characters, fruit anatomical features can be useful at the generic and specific levels.