Revision of the South American species of the genus Piptochaetium (Poaceae, Pooideae, Stipeae)

Abstract

This paper deals with a taxonomic revision of the South American species of the genus Piptochaetium. This systematic treatment ineludes a discussion of the morphological and anatomical characteristics of the genus, together with a key to identify the species treated in 2 sections: Podopogon (Raf.) Parodi (13 species) and Piptochaetium (14 species, 2 subspecies and 2 varieties). For each species, a description, synonymy, geographical distribution, illustrations and photographs of the characters with taxonomical value are given. Some species, varieties or forms have been reduced to synonymy: P. panicoides f. subpapillosum, P. grisebachi, P. stipoides var. chaetophorum, P. stipoides var. parviflorum, P. stipoides var. purpurascens, P. stipoides var. verruculosum and P. uruguense var. microcarpum