Alternanthera

Scientific name

Alternanthera Forssk.

Common names

temple plant

Family

Amaranthaceae

Native distribution

Northern Hemisphere

Species commonly cultivated

Alternanthera aquatica (D. Parodi) Chodat (South America)
A. reineckii Briq. (and varieties) (South America)
A. sessilis (L.) DC. (and varieties) (pan-tropical)

U.S. Federal Noxious Weed: Alternanthera sessilis

Identification: A. sessilis is unique in the genus; the persistent perianth segments on the fruit are shorter than (rarely barely as long as) the heart-shaped, one-seeded fruit.

See Alternanthera sessilis disseminule fact sheet.

Adventive distribution

Alternanthera philoxeroides (Mart.) Griseb. and A. sessilis have become established in most tropical, subtropical and even some temperate regions of the world.

Weed status

Alternanthera philoxeroides is considered a serious environmental weed throughout its adventive range. Alternanthera sessilis is an aquatic weed on the U.S. federal noxious weed list. Several other species of Alternanthera are also occasionally recorded as weedy.

Habit

erect and creeping, submersed and mostly emergent stem plant

Brief description

Perennial. Decumbent, with erect and creeping stems; adventitious roots produced from individual nodes along stem as it lengthens; creeping (floating) stems may swell with aerenchyma for buoyancy. Leaves opposite, decussate, sessile, lanceolate, ovate or obovate. Inflorescence axillary or terminal, of sessile or stalked, typically white, pink or purple heads. Perianth segments 5. Reproduces by seeds or stem fragments.

Natural habitat

inhabits rivers, lakes, swamps; occasionally terrestrial

Additional comments

Alternanthera comprises approximately 80-100 species, mostly from South America. The identity of species presently traded in the aquarium and pond plant industries is vague, with numerous varieties being produced and sold under commercial and existing taxonomic names (e.g. 'Lilacina' and ‘Rosaefolia’).