Ottelia

Scientific name

Ottelia Pers.

Common names

duck lettuce, santawaa, water plantain

Family

Hydrocharitaceae

Similar genera

Aponogeton, Damasonium, Echinodorus, Hydrocleys

Native distribution

Africa, Asia, Australia, and South America

Species cultivated

Ottelia alismoides (L.) Pers.

O. mesenterium (Hallier fil.) den Hartog

O. ovalifolia (R. Br.) Rich.

O. ulvifolia (Planch.) Walp.

U.S. Federal Noxious Weed: Ottelia alismoides

Identification: Ottelia alismoides is distinguishable from most Ottelia species by its large, light green, ovateovate:
(adj) egg-shaped in outline; generally with the broad end at or near the base
to rounded leaves with undulateundulate:
(adj) (of, e.g., a margin) with a wavy surface; wavy in the vertical (up and down) plane
margins in mature plants, lack of floating leaves, and white flowers with yellow center.

See Ottelia alismoides disseminule fact sheet.

Adventive distribution

Ottelia alismoides is introduced in several states in the southern United States. Ottelia ovalifolia is introduced in New Zealand; its presence in New Caledonia is not confirmed.

Weed status

Ottelia alismoides is an aquatic weed on the U.S. federal noxious weed list.

Habit

large, submersedsubmersed:
see submerged
or floating, attached rosetterosette:
(n) a radiating cluster of leaves, usually close to the ground at the base of a plant
plant

Brief description

Annual or perennialperennial:
(adj) (of a plant) having a life cycle of more than two years
. Monoeciousmonoecious:
(adj) having separate male and female flowers on the same individual
or dioeciousdioecious:
(adj) having separate male and female flowers on different individuals of the same species
. Stem typically compact, roots unbranched. Leaves in a basalbasal:
(adj) at or pertaining to the base, or point of attachment
rosette, sheathed at base, juvenile leaves usually sessilesessile:
(adj) attached directly, without a stalk
, mature leaves numerous, often petiolatepetiolate:
(adj) relating to or in the form of a petiole; bearing petioles
, submersedsubmersed:
see submerged
and/or floating; mature leaf bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
linear, reniformreniform:
(adj) kidney-shaped
to orbicularorbicular:
(adj) circular in outline
, veins parallel or palmatepalmate:
(adj) (of leaves or venation) with lobes, leaflets, divisions or veins originating from the same point
; base rounded to cordatecordate:
(adj) heart-shaped; in the form of two rounded lobes
; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
or undulateundulate:
(adj) (of, e.g., a margin) with a wavy surface; wavy in the vertical (up and down) plane
. Spathespathe:
(n) a large bract or bracts subtending and often enclosing an inflorescence
of 2 united bracts, often winged or ribbed. Flowers unisexualunisexual:
(adj) (of a flower) with either stamens (male) or pistils (female) but not both; consisting of only male or female flowers
or bisexualbisexual:
(adj) having both male and female sexual reproductive structures on one individual or in one flower
; female and bisexualbisexual:
(adj) having both male and female sexual reproductive structures on one individual or in one flower
flowers sessilesessile:
(adj) attached directly, without a stalk
, solitary; male flowers numerous, pedicellatepedicellate:
(adj) borne on a pedicel
, emerging from spathespathe:
(n) a large bract or bracts subtending and often enclosing an inflorescence
; sepals 3, green; petals 3, conspicuous, yellow, purple, white or pink, or reduced in cleistogamouscleistogamous:
(adj) (of flowers) remaining closed, self-pollinating, and setting fertile seed
flowers. Dispersal by numerous seeds.

Natural habitat

usually in slower waters of rivers, lakes, and ponds

Additional comments

Ottelia contains 19 species; 11 species in Africa, seven in Asia and Australia, and a single species in South America. A great deal of taxonomic confusion is associated with this genus due to the high degree of polymorphism in several species, especially O. alismoides. Although robust plants of Ottelia occur in the wild, only a few species (or varieties) are suitable for aquarium or pond cultivation, and they remain difficult species to maintain in permanent culture.