cf. Cenchrus pennisetiformis
The Poaceae (also called Gramineae or true grasses) are a large and nearly ubiquitous family of monocotyledonous flowering plants. With more than 10,000 domesticated and wild species, the Poaceae represent the fifth-largest plant family, following the Orchidaceae, Asteraceae, Fabaceae, and Rubiaceae. Though commonly called "grasses", seagrasses, rushes, and sedges fall outside this family. The rushes and sedges are related to the Poaceae, being members of the order Poales, but the seagrasses are members of order Alismatales.