Sphenoclea

Scientific name

Sphenoclea Gaertn.

Common names

chickenspike, wedgewort, gooseweed

Family

Sphenocleaceae

Similar genera

Anemopsis, Ipomoea

Native distribution

pantropical

Species cultivated

not currently cultivated

Adventive distribution

Sphenoclea zeylanica Gaertn. is introduced into the United States.

Weed status

Sphenoclea zeylanica can be a troublesome weed in rice worldwide.

Habit

semi-aquatic stem plant; seasonally submerged, emergent or temporarily terrestrial

Brief description

Small to medium herb or shrub. Roots thread-like. Stem erect, branched, ± succulent, hollow, base thickened, glabrous. Leaves alternate; subsessile to petiolate; leaf blade lanceolate-elliptic to obovate-elliptic; base tapering; margin entire; glabrous. Inflorescence a terminal, dense spike; pedunculate; bracts spathulate, inflexed; bracteoles broadly linear. Flowers actinomorphic, small; sessile; only a few opening at a time. Calyx basally connate, 5-lobed, lobes obovate to triangular, imbricate, persistent; corolla campanulate, 5-lobed, lobes ovate-triangular, imbricate, usually white, or pink; stamens 5, alternating with petals; style 1, short; stigma capitate to obscurely 2-lobed; ovules numerous.

Natural habitat

in damp to wet places; prefers stagnant water, tolerant of brackish water; along ponds, rivers, marshes, in periodically inundated swamps, also in rice fields

Additional comments

Sphenoclea contains just two species: Sphenoclea zeylanica Gaertn. and Sphenoclea pongatium A. DC.