The family Poaceae on Morro Santana, Rio Grande do Sul, Brazil

Abstract

A floristic survey of the family Poaceae (Gramineae) on Morro Santana, Rio Grande do Sul, Brazil, was carried out. The work was based on intensive field collections and revision of herbaria. A hundred and twenty-four species were confirmed, distributed in 54 genera and eight subfamilies. The studied area contains near a quarter of the estimated grass diversity for the State of Rio Grande do Sul. Panicoideae (65 species) is the most representative subfamily, including over half of the species. The other species are divided among the subfamilies Pooideae (28), Chloridoideae (18), Aristidoideae (seven), Bambusoideae (two), Ehrhartoideae (two), Danthonioideae e Pharoideae (one species each). A hundred and thirteen species are native (91%) and 11 are exotic (9%). Morro Santana contains a great grass richness and it is a very important area for conservation in the city of Porto Alegre. A checklist of the confirmed species, analytical keys for genera and species as well as illustrations are provided.