Present on Pacific Islands?  yes

Threat only at high elevations?  no

Habit:  herb

Description:  "Probably perennial.  Stems prostrate, decumbent, or ascending, richly branched, mostly 0.2-1.0 m tall, striate, more or less densely pubescent with abietiform trichomes, older stems subglabrous, internodes generally 3-12 cm long.  Leaves short-petiolate, petiole generally 3-5 mm long, not distinct from blade, blade ovate to oblong-ovate or elliptic, acute to short-cuspidate and mucronate at apex, cuneate at base and tapering along petiole, mostly with 5-8 main secondary veins on each side of midrib, young leaves densely pubescent below with branched and abietiform hairs, less pubescent above, older leaves becoming glabrescent, fully developed leaves 3-7 cm long, 1-5 cm wide.  Inflorescences axillary, heads single or 2 or 3 together, rounded or short-cylindric, 6-10 mm wide, white or stramineous.  Bract ovate, strongly concave, sharply acute with prominent midrib, glabrous, 2.5-3.5 mm long.  Bracteoles longer than bract, more than half as long as tepals, strongly flattened laterally and sharply keeled, keel pubescent with scaberulous trichomes.  Flower sessile within bracteoles.  Tepals 5, unequal in size, dissimilar in shape; outermost tepals lanceolate, 4.5-6.5 mm long, glabrous or pubescent near base, becoming tough, hardened and sulcate at base with several prominent ribs, dorsal tepal lanceolate or oblong-lanceolate, stiff, flattened, with several parallel ribs, thre of which are more distinct than the others, innermost (=lateral) tepals shorter, folded and sharply keeled.  Staminal tube 3-4 mm long, cleft to about 4/5 or more of its entire length; stamens 5, filaments narrowly strap-shaped, anthers oblong, 1.5-2.0 mm long; pseudostaminodia strap-shaped, narrow, laciniate at apex, about as long as stamens.  Ovary rather abruptly narrowed into a distinct style, stigma capitate, penicillate. 

var. ecuadoriensis:  "Differs from var. albotomentosa in sparsely pubescent to subglabrous stems; pubescence, when preseent, nowhere completely covering or concealing the stem.  Agrees in habit and floral characteristics with var. albotomentosa" (Eliasson, 1969; pp. 68-71).

Habitat/ecology:  In Peru (Dept. Lima), "open rocky slopes, 1800-2000 m" (Eliasson, 1969; pp. 68-71).

Propagation:  Seed

Native range:  Ecuador and Peru (Eliasson, 1969; pp. 68-71).

Presence:

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Ecuador (Mainland) Ecuador	Ecuador (Republic of) (continental)	native	Eliasson, Uno (1987) (p. 69)
Perú Perú	Perú (Republic of)	native	Eliasson, Uno (1987) (p. 69)

Comments:  Reported as possibly an invasive plant in the Galápagos Islands per Charles Darwin Research Station.

Additional information:
Additional online information about Alternanthera albotomentosa is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Alternanthera albotomentosa as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Alternanthera albotomentosa may be available from the Germplasm Resources Information Network (GRIN).

References:

Eliasson, Uno. 1987. Amaranthaceae [44.]. Flora of Ecuador 28. 138 pp.