Rhynchospora rugosa, known by the common name of claybank beaksedge, is a member of the sedge family, Cyperaceae. It is a perennial herb, native to Central and South America.

Four subdivisions are accepted.

• Rhynchospora rugosa subsp. americana (Guagl.) Govaerts – southeastern Mexico, Central America, and Andean and southern South America
• Rhynchospora rugosa subsp. lavarum (Gaudich.) T.Koyama – Hawaiian Islands
• Rhynchospora rugosa f. ponapensis (Hosok.) T.Koyama – Caroline Islands (Pohnpei)
• Rhynchospora rugosa subsp. rugosa – Central Mexico to Central America, the Caribbean, and tropical South America

While Plants of the World Online accepts the African Rhynchospora brownii as an extant species, it is considered to be a subspecies of Rhynchospora rugosa by the Global Biodiversity Information Facility.

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