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 plantstem plant:
(n) (a term used in the aquarium and pond plant trade) having an elongate stem (as opposed to a compact stem)
; seasonally submergedsubmerged:
(adj) (syn. submersed) under water; submerged below the water surface
, emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
or temporarily terrestrial

Brief description

Small to medium herb or shrub. Roots thread-like. Stem erect, branched, ± succulent, hollow, base thickened, glabrousglabrous:
(adj) without hairs or scales
. Leaves alternatealternate:
(adj) (of leaves) bearing one leaf per node; placed singly on the stem at different heights
; subsessile to petiolatepetiolate:
(adj) relating to or in the form of a petiole; bearing petioles
; leaf bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
lanceolate-elliptic to obovate-elliptic; base tapering; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
; glabrousglabrous:
(adj) without hairs or scales
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
a terminalterminal:
(adj) at the apex
, dense spikespike:
(n) an indeterminate, unbranching inflorescence of sessile flowers or flower clusters on a usually elongated axis
; pedunculatepedunculate:
(adj) borne on or possessing a peduncle
; bracts spathulatespathulate:
(adj) (or spatulate) spoon-shaped
, inflexedinflexed:
(adj) curved or bent inwards toward the axis
; bracteoles broadly linear. Flowers actinomorphicactinomorphic:
(adj) of flowers, having radial symmetry; capable of being bisected into identifical halves along more than one axis
, small; sessilesessile:
(adj) attached directly, without a stalk
; only a few opening at a time. Calyxcalyx:
(n) the outer whorl of the perianth; all the sepals of a flower
basally connateconnate:
(adj) of plant parts congenitally united into a single structure
, 5-lobed, lobes obovateobovate:
(adj) ovate, with the narrow end at the base
to triangular, imbricateimbricate:
(adj) overlapping like shingles on a roof
, persistentpersistent:
(adj) (of leaves etc,) remaining attached; not being dropped or falling off
; corollacorolla:
(n) the inner whorl(s) of the perianth; all the petals of a flower
campanulatecampanulate:
(adj) bell-shaped
, 5-lobed, lobes ovate-triangular, imbricateimbricate:
(adj) overlapping like shingles on a roof
, usually white, or pink; stamens 5, alternating with petals; stylestyle:
(n) in a flower, the narrow and elongated part of the pistil between the stigma and the ovary
1, short; stigmastigma:
(n) the portion of the pistil that is receptive to pollen
capitatecapitate:
(adj) terminated by an enlarged and rounded head
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.