South America has 234 genera of Poaceae with native species in 11 of 12 subfamilies; in 7 of them Brazil has the primacy in number of genera, with these groups adding up to 136 genera on the continent, 125 in Brazil and 11 absents: five Bambusoideae (where Brazil has 12 endemic genera) and six in Panicoideae (Brazil with 7 endemic genera). The status of the 4 other families are detailed below.
Danthonioideae (19/285) has three genera in South America, Cortaderia Stapf. and Danthonia DC occur in Brazil; Rytidosperma Stued. occur from Malesia to Australasia, Hawaiian Islands, Easter Island and S. South America in Argentina and Chile.
Arundinoideae (11-13/35-38) is a subfamily with a single representative in the Americas, P. australis (Nees) Döll, which curiously occurs in all countries of the Hemisphere, except for the Caribbean islands, Brazil and Paraguay, this being genus probably the most distributed of all the New World genera absent in the country. None of the major platforms (POWO, VPA, WCSPF, Reflora) marks this genus in Brazil. Beauty images of this species in French Guiana can be seen at La Chaussete Rouge (SEE).
Phragmites australis is a cosmopolitan species that has strong effects on the ecosystems it inhabits; it therefore can offer valuable insights into plant responses to global change, with three welll defined lineages, possibly more (Eller et al., Frontiers, 2017); It is a robust and highly productive grass in the Poaceae family that occurs in a wide range of freshwater and brackish wetlands. GBIF shows 7 records of this species in Brazil (SEE), in SE & S Rio de Janeiro to E São Paulo states, also a isolated record in western region of latter states, which are marked on the more general map of the species, which strongly agrees with the maps present in POWO, if we consider all 7 records as insufficient to attest to their native status in the country.
In Chloridioideae, South America has 39 genera; Argentina and Brazil lead in generic diversity, with 28 (Blepharidachne, Scleropogon, Tragus and Willkommia are highly disjuncts, Neobouteloua endemic) and 21 (Triraphis highly disjunct; three endemics), respectively.
Pooideae has 55 genera in South America, only 25 in Brazil. The highest diversity are from Argentina, with 39 genera, Chile 37, Peru 35, Bolivia 32, Colombia and Ecuador 31. For species, South America has 847 spp., only 99 in Brazil, 25 endemics.
Four lineages of Pooideae ocur in South America, four in Brazil (numbers at parenthesis): Meliceae (2/13 spp.), Stipeae (3/32 spp.), Brachypodieae (absent), Triticeae (2/5 spp.) and Poeae (18/48 spp.). Excepting Brachypodieae, all subtribes absents in Brazil belongs Poeae.
Poeae has 16 subtribs in South America, nine absents in Brazil.