Cyperaceae
Cyperaceae Juss. comprises approximately 95–100 genera and 5,500–5,800 species, making it one of the largest monocot families worldwide. Molecular phylogenetic studies have refined the circumscription of several genera, particularly Carex, Cyperus, Eleocharis, Fimbristylis, and Schoenoplectus, while confirming the family's monophyly. Cyperaceae is readily recognized by its usually solid, triangular stems, closed leaf sheaths, reduced wind-pollinated flowers, and dry one-seeded fruits (achenes).
Key characteristics
- Annual or perennial herbs
- Culms usually solid and triangular ("sedges have edges")
- Leaves narrow, tristichous, with closed sheaths
- Nodes inconspicuous
- Flowers minute and wind-pollinated
- Superior ovary
- Fruit a one-seeded achene
Distribution
Cyperaceae has a nearly cosmopolitan distribution, occurring on every continent except Antarctica. The family is especially abundant in wetlands, marshes, swamps, riverbanks, lakeshores, peatlands, alpine meadows, grasslands, and tropical forests, although numerous species are adapted to deserts, saline habitats, and high mountain ecosystems. Cyperaceae is widely distributed throughout the Himalayan, Karakoram, and Hindu Kush mountains, Upper and Plains, Potohar Plateau, Salt Range, western dry mountains, Lower Indus Plain, wetlands, riverine forests, and the deserts of Cholistan, Thal, and Thar. Species occur in marshes, irrigation canals, rice fields, lakes, streams, alpine meadows, saline flats, sandy soils, and agricultural lands. The family is particularly diverse in freshwater wetlands and high-altitude ecosystems.