A new species of Poaceae, Paspalum volcanensis, from southern Bolivia and n
orthwestern Argentina, is described and illustrated. Its concavoconvex spik
elets and upper lemma with conspicuous nerves are characters it shares with
other species of subgenus Anachyris of Paspalum. A key to the species of t
he subgenus and comments on the delimitation of the new species are provide
d here.