Hydrocharis

Scientific name

Hydrocharis L.

Common names

frogbit, kilpukka, floating frogbit

Family

Hydrocharitaceae

Similar genera

Heteranthera (some), Hydrocleys, Limnobium, Limnocharis

Native distribution

Europe, Asia, Africa

Species cultivated

Hydrocharis dubia (Blume) Backer

H. morsus-ranae L.

Adventive distribution

Hydrocharis morsus-ranae is introduced into the United States, Australia, and Canada.

Weed status

Hydrocharis dubia Backer and H. morsus-ranae are considered weeds in several countries.

Habit

creeping, stoloniferous plant with floating and emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
leaves

Brief description

Perennial. Stolons creeping, originating from leaf axils. Stipules distinctive. Leaves floating or emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
, in rosettes widely spaced along stolonstolon:
(n) an above-ground stem growing more or less horizontally and often forming adventitious roots at the nodes
, 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)
ovate to orbicularorbicular:
(adj) circular in outline
, venationvenation:
(n) the arrangement of veins in a leaf
palmatepalmate:
(adj) (of leaves or venation) with lobes, leaflets, divisions or veins originating from the same point
with cross-veins; base cordatecordate:
(adj) heart-shaped; in the form of two rounded lobes
to reniformreniform:
(adj) kidney-shaped
; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
; aerenchymaaerenchyma:
(n) plant tissue with large, gas-filled intercellular spaces that facilitates gaseous exchange and maintains buoyancy
present at base of leaf. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
subtended by spathespathe:
(n) a large bract or bracts subtending and often enclosing an inflorescence
of 1 or 2 bracts. Flowers unisexualunisexual:
(adj) (of a flower) with either stamens (male) or pistils (female) but not both; consisting of only male or female flowers
; male flowers sessilesessile:
(adj) attached directly, without a stalk
, 1-4 per spathespathe:
(n) a large bract or bracts subtending and often enclosing an inflorescence
; female flowers pedicellatepedicellate:
(adj) borne on a pedicel
, solitary; sepals 3; petals 3. Dispersal by seed and stem fragments.

Natural habitat

shallow waters of swamps, ponds, and lakes

Additional comments

Hydrocharis dubia is considered threatened in some regions of the world and weedy in others. Hydrocharis chevalieri (de Wildeman) Dandy is a mostly emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
, African species that is not cultivated at present.