Calystegia
Accepted name/Authority/Place of publication:
CALYSTEGIA R. Brown, Prodr. 483. 1810,
Tribe:
Convolvuleae
Habit:
Herbs prostrate or erect to twining to several meters tall, rhizomatous or [in North America] woody at base.
Leaves:
Leaves nearly sessile to petiolate, oblong to hastate or sagittate or rarely pedate [in North America].
Inflorescences:
Inflorescences axillary
Flowers:
1-flowered or [in North America] few flowered cymes; bracteoles 2, sepal-like, inserted immediately below calyx, ovate and sometimes saccate, enclosing calyx, or [in North America] remote from calyx and subulate or leaf-shaped, persistent. Sepals nearly equal, persistent. Corolla white or pink or [in North America] pale yellow, funnelform, with 5 distinct midpetaline bands, glabrous. Stamens included, equal. Pollen globose, pantoporate, not spiny. Ovary 1-loculed, 4-ovuled; style 1, included in corolla; stigmas 2, clavate.
Pollen:
Pollen globose, pantoporate, not spiny
Fruits:
Capsule globose, glabrous, indehiscent
Seeds:
Seeds 4, smooth or minutely tuberculate
Distribution:
Mostly temperate regions but sparinly extending to the tropics. map
Number of Species:
25
Infrageneric Characters:
Approximately 70 intergrading subspecific taxa which can be arbitrarily combined into about 25 species: mostly temperate but sparingly extending to the tropics.
Contributors:
Nearly all taxa in the genus intergrade geographically into neighboring taxa with the exception of the widespread coastal species, Calystegia soldanella (L.) R. Br. Almost half of the genus is endemic in California, U.S.A.; the exceptions noted in the generic description as "in North America" all refer to the Californian endemics. It is impossible to draw clearly defined specific limits, and intermediate forms are always found where two taxa approximate geographically.