Alternanthera ficoidea

Content

Description

Spreading to ascending woody herb; young stems rooting at nodes, either glabrous or densely pubescent all-round or in 2 lines. Petiole less than 1 cm long; blade ovate to elliptical, 2-9 x 0.5-4 cm, apex acute to acuminate, mucronulate, cuneate at base, glabrous to sparsely pubescent, becoming glabrescent, hairs simple or branched near base. Inflorescence axillary or terminal, sessile heads; heads globose, 3-10 mm wide; bracts and bracteoles white, hyaline, spreading, subequal, ovate to elliptic-lanceolate, 1.5-3.5 mm long, acuminate, aristate, pubescent. Tepals rigid, ovate to elliptical, 3.7-4.5(-5) mm long, acuminate, mucronate or cuspidate, brown to green below, becoming white above, hispidulous, prominently 3-veined, inner 2 tepals navicular; anthers oblong, pseudostaminodia longer than stamens, fimbriate or lacerate apically; style slender, ca. 0.3 mm long, stigma capitate. Utricle ovoid or suborbicular; seed dark reddish-brown, lenticular or cochleate, 1 x 1 mm.

Distribution

Guianas present, South America present, Southern America: Panamá (Panamá present)

West Indies, Panama to South America; 89 collections studied, all from the Guianas (GU: 4; SU: 38; FG: 47).

Common Name

English (Suriname): akwemma

Notes

Since Veldkamp’s proposal () to reject Alternanthera ficoidea (L.) P. Beauv. in favour of A. tenella Colla, the latter name came in use. At the Berlin Congress (1987), however, the possibility to conserve species names was accepted. The ultimate decision at the Tokyo Congress (1993) was to conserve Gomphrena ficoidea with a conserved type. This implies that the recently reintroduced name A. tenella should disappear in synonymy, and we can continue with the name that in the Guianas always has been used for this species.
The characteristics of a large species-complex including A. ficoidea and A. halimifolia, which occurs over much of South America and shows variation in simple vs. branched trichomes, length and apex of bracts and sepals; and inflorescence length, are discussed in detail under A. tenella by Kellogg (1988); see also note below under A. halimifolia.
The neotropical species A. paronychioides A. St.-Hil. is often reported from the Guianas, but no specimens have been encountered in this study. While it may be expected in the Guianas, numerous Guianan specimens of the very similar A. ficoidea misidentified as A. paronychioides were found. In A. paronychioides there are 2 pairs of leaves clustered beneath the inflorescence-head and the bracteoles are ovate, to 2 mm; whereas in A. ficoidea there is only one pair of leaves beneath the inflorescence-head and the bracteoles are elliptic-lanceolate, 3.7-4.5 mm long.
Collections of amaranths from the Guianas may sometimes include a cultivated variant of A. ficoidea, known as "calico plant", having variegated leaves blotched with red, yellow, orange and/or purple. This A. ‘Bettzickiana’ is grown in the 3 Guianas (GU: Pomeroon Distr., de la Cruz 1078; SU: Paramaribo, Samuels s.n.; FG: Saül, Mori et al. 18780).
The Bettzickiana plants have leaves narrowly spathulate, and should not be confused with the very similar A. ficoidea ‘Amoena’ having the same colors of variegation as Bettzickiana but with leaves lanceolate or elliptical. The Amoena ("parrotleaf") plant is cultivated and sometimes naturalized in the 3 Guianas (DeFilipps, 1992) [corroborated by SU: Paramaribo, Maguire & Stahel 22715a; FG: Ile Royale, Feuillet 2175], in SU it is known as "Ceylongras" (Ostendorf, 1962).