List of Poaceae genera

Poaceae, also known as the true grasses, is the fourth largest plant family in the world with around 12,000 species and roughly 800 genera.

Grasses probably originated in the understory of tropical rainforests in the Late Cretaceous, but have since come to occupy a wide range of different habitats.

[3][4] Notably, they are the dominant species in grasslands, open habitats that cover around one fifth of the earth's terrestrial surface.

[3] The C4 photosynthetic pathway has evolved at least 22 times independently in the grasses; C4 species are more competitive than C3 plants in open habitats with high light intensity and warm temperatures.

Most of the diversity falls into the two big BOP and PACMAD clades, which each contain roughly half of the family's species.