Muhlenbergia tenuissima (Presl) Kunth, Enum. Pl. 1: 198. 1833.

Discussion.

This taxon is a distinctive species which seems to be restricted to chalky limestone flats usually occurring as a dense carpet on clay-like soils in open savannahs; known from North America and Central America (Peterson and Annable 1991; Brako and Zarucchi 1993). Although previously included for Peru in Hitchcock (1927), Standley (1936) and Tovar (1993), the specimens cited are M. ciliata without prominent cilia along the lateral veins (see discussion of M. ciliata).