Anatomical and Micromorphological Studies of Chusquea Subg. Magnifoliae and Chusquea Subg. Platonia (Poaceae, Bambusoideae, Bambuseae)

Abstract

Premise of research. Chusquea Kunth is the most diverse bamboo genus worldwide and comprises 198 species classified into five subgenera. Chusquea subg. Magnifoliae and Chusquea subg. Platonia together include 26 taxa that have been studied on the basis of incomplete or fragmentary material, and complete keys to their taxonomic identification based on vegetative and reproductive characters are still pending. Since the identification of woody bamboos often relies mainly on vegetative characters, the addition of foliage leaf blade anatomy and micromorphology characters provides valuable information to be considered. Methodology. Anatomical and micromorphological studies were performed on the basis of herbarium material. Foliage leaf blade abaxial epidermal and transverse section characters are described and compared for 11 taxa of Chusquea subg. Magnifoliae and 14 of Chusquea subg. Platonia to enhance the currently available descriptions. Pivotal results. Regarding foliage leaf blade anatomy in transverse section, no single character turned out to be exclusive to a species or subgenus. All taxa studied here are recognizable from a combination of anatomical characters. Of note is that intercostal sclerenchyma is recorded for the first time in the subtribe Chusqueinae. When micromorphological characters of the foliage leaf blade abaxial epidermis are considered, a few potential autapomorphies may be recognized for a few species. Conclusions. On the basis of anatomical and micromorphological studies, characters of taxonomic value are presented in comparative tables. A key to the identification of the species of Chusquea subg. Magnifoliae and Chusquea subg. Platonia was elaborated and is presented here for the first time as an additional tool to corroborate the taxonomic identity of sterile or poorly collected specimens.