Tropical Amaranth

Amaranthus berlandieri often has been recognized as a separate species related to A. polygonoides. J. Henrickson (1999) clarified the confusion that existed in earlier descriptions of these two taxa and showed that the main characters used for their separation (dehiscent versus indehiscent utricles, leaf shape, etc.) are inconsistent and cannot be applied for segregation of two independent species. The subspecies rank may be more appropriate for A. berlandieri, as was suggested by A. Thellung (1914-1919). The relationships between these taxa of the A. polygoniodes aggregate require additional study; in the present treatment we follow the solution proposed by Henrickson.

Plants annual, glabrescent proximally, pubescent distally, becoming glabrous at maturity. Stems erect-ascending to pro-strate, branched mostly at base and in proximal ¹/2, 0.1-0.5 m. Leaves: petiole ± equaling blade; blade ovate, obovate-rhombic to narrowly ovate, sometimes lanceolate, 1.5-3(-4) × 0.5-1.5(-2) cm, base cuneate, margins entire to undulate-erose, apex rounded, obtuse, or emarginate, mucronate. Inflorescences axillary, congested clusters. Bracts of pistillate flowers lanceolate or linear, 1-1.5 mm, ¹/2 as long as tepals. Pistillate flowers: tepals 5, connate in proximal ¹/3 (entirely distinct in all other species), with 3 prominent veins abaxially, spatulate or somewhat clawed, equal or subequal, 2-3 mm, apex rounded or retuse, mucronate; style branches somewhat spreading; stigmas 3. Staminate flowers intermixed with pistillate; tepals (4-)5; stamens 2-3. Utricles cylindric or narrowly turbinate, 2-2.5 mm, ± equaling tepals, smooth proximally or roughened toward tips, indehiscent or tardily dehiscent. Seeds dark reddish brown to black, lenticular, 0.8-1 mm diam., shiny.

Fla., S.C., Tex.; Mexico; West Indies; n South America; rarely introduced in Europe and some other regions.

Flowering summer-fall.

Disturbed habitats, coastal areas, near wool-combing mills; 0-500m.

Amaranthus berlandieri (Moquin-Tandon) Uline & W. L. Bray

Amaranthus berlandieri (Moq.) Uline & Bray, Bot. Gaz. 19:
268. 1894.
Sarratia Berlandieri Moq. in DC. Prodr. 13 2 ; 268. 1849.
Stems slender, fleshy, ascending or prostrate, 5-30 cm. long, much branched from the base, villoustomentose, especially about the inflorescence; leaves crowded near the ends of the stems, soon deciduous below, the petioles 3-11 mm. long, the blades oblong-lanceolate to oblanceolate, 6-20 mm. long, broadly rounded at the apex or obtuse and usually emarginate, cuneate at the base and decurrent, , glabrous, or sparsely pubescent when young, bright-green; flowers monoecious, in dense several-flowered sessile axillary clusters; bracts lanceolate, spinetipped, usually half as long as the sepals or less; sepals of the pistillate flowers spatulate, 2 mm. long, rounded at the apex, united for one third their length, the tube not constricted; sepals of the staminate flowers lance-oblong, acuminate; stamens 2; style-branches 3; utricle turbinate, thin-walled, indehiscent, about equaling the sepals; seed obovoid, black and shining, 0.8 mm.long.
Type locality: Between San Antonio, Texas, and Matamoros, TamauKpas. Distribution : Central and western Texas.

Amaranthus polygonoides L. PL Jam. Piigill. 27. 1759
Roemeria polygonoides Moench, Meth. 341. 1794.
Amblogyna polygonoides Raf. Fl. Tell. 3: 42. 1837.
Albersia polygonoides Kunth, Fl. Berol. ed. 2. 2: 144. . 1838.
Amaranthus verticillatus Pavon; Moq. in DC. Prodr. 13 2 : 270, as synonym. 1849.
Sarratia polygonoides Moq. in DC. Prodr. 13 2 : 270, as synonym. 1849.
Stems slender, ascending or spreading, 1-5 dm. long, much branched from the base, villous about the inflorescence; leaves rather distant, not crowded, the petioles 2-7 mm. long, slender, the blades 0.6-2 cm. long, rhombic-ovate to obovate or oval, obtuse to subtruncate and usually emarginate at the apex, acute or cuneate at the base and decurrent, pale-green, glabrous, or sparsely pubescent beneath; flowers monoecious, in dense sessile several-flowered axillary clusters; bracts lanceolate, acuminate, half as long as the sepals or less; sepals of the pistillate flowers spatulate, erect, obtuse or rounded, often apiculate, 3-nerved, scarious, Pam 2, 1917] AMARANTHACEA3 105
i
united at the base; sepals of the staminate flowers oblong, acute; stamens 2 or 3; style-branches 2 or 3; utricle ovoid or turbinate, circumscissile, thin-walled; seed black or dark-brown, shining, 0.6-0.9 mm. in diameter.
Type locality: Jamaica.
Distribution: Florida, Texas, and the West Indies; Mexico to northern South America.

Amaranthus polygonoides is a species of flowering plant found in North America and the Caribbean. It goes by the common name of tropical amaranth.