Cyperus pseudothyrsiflorus is a plant species native to Nuevo León, New Mexico and Texas, a member of Cyperus subgenus Cyperus. It occurs in cultivated fields and other disturbed areas at elevations of less than 1000 m (3400 feet). Cyperus pseudothyrsiflorus is a perennial herb spreading by underground rhizomes. Stems are triangular in cross-section, up to 40 cm (16 inches) tall. It is closely related to C. retroflexus and considered a variety of that species by some authors.