Josiah Amaranth

According to J. D. Sauer (1972b), Amaranthus myrianthus Standley most probably is a hybrid between A. arenicola and A. greggii.

Plants glabrous or glabrescent. Stems erect to ascending, much-branched from base, 0.3-1 m. Leaves: petiole shorter than blade; blade ovate, or rhombic-ovate to elliptic, 1.5-4 × 0.5-2 cm, thick, coarse, base cuneate to rounded, margins entire, plane or irregularly undulate, apex rounded-obtuse to emarginate, with terminal mucro. Inflorescences mostly terminal, spikes to panicles, usually erect, thick, flexible. Bracts: of pistillate flowers with short, excurrent midrib, 1.5-2.5 mm, shorter than tepals, apex acute or acuminate; of staminate flowers shorter than tepals, apex acute. Pistillate flowers: tepals with dark, prominent midrib not excurrent, spatulate, subequal, 2-3 mm, apex obtuse to subacute, with terminal mucro; style branches spreading; stigmas 3. Staminate flowers: tepals 5, equal, 2-3 mm, apex obtuse to subacute; inner tepals: with apex indistinctly mucronulate; stamens 5. Utricles light brown, elliptic, 3 mm, equaling tepals, walls somewhat fleshy, smooth, indehiscent. Seeds dark brown, 1.2-1.7 mm diam., shiny.

La., Tex.; Mexico.

Flowering summer-fall.

Coastal sand dunes, sea beaches; 0-50m.

Amaranthus myrianthus Standley, Bull. Torrey Club 41: 506
1914.
Amaranthus Greggii Muelleri Uline & Bray, Bot. Gaz. 19: 272. 1894.
Stems prostrate or ascending, 3-10 dm. long, much branched, stout, succulent, glabrous or sparsely villous; petioles stout, 4—15 mm. long; leaf-blades rounded-oval to oval or nearly orbicular, 6-20 mm. long, 5-15 mm. wide, rounded or emarginate at the apex, rounded to cuneate at the base, thick and firm, very conspicuously veined, villous beneath, at least when young; inflorescence dioecious, of numerous paniculate many-flowered spikes, these dense or sometimes interrupted below, 6-40 cm. long and 1-2 cm. thick in the pistillate plants, the spikes of the staminate plants shorter, somewhat interrupted, few-flowered, 7 mm. or less in diameter; bracts 2 or 3 at the base of each flower, ovate or broadly ovate, acute, sometimes pungent-tipped, usually half as long as the sepals but sometimes nearly equaling them ; sepals of the staminate flowers oblong to oval, 2.5 mm. long, obtuse, apiculate, thin and scarious except along the single green nerve; sepals of the pistillate flowers 2 mm. long, spatulate, or narrowly oblong and narrowed toward the base, broadly obtuse to acutish, glabrous, rather thick and firm, much thickened and united at the base, the midnerve usually excurrent; stamens 5; style-branches 3, slender, elongate, divaricate; utricle obovoid, about equaling the sepals, thin-walled, nearly smooth, circumscissile; seed rotund, black and shining, about 1 mm.
in diameter.
Type locality: Vicinity of I,a Barra, 8 km. east of Tampico, Tamaulipas. Distribution: Seashores, Tamaulipas to Vera Cruz.

Amaranthus greggii S. Wats. Proc. Am. Acad. 12: 274. 1877
Stems stout, spreading or ascending, 3—9 dm. long, branched, striate, . green, glabrous below, sparsely villous about the inflorescence; petioles stout, 5-18 mm. long; leaf -blades oblong to oval or rhombicovate, 1.2-3.5 cm. long, rounded at the apex, acute to rounded at the base, thick and fleshy, deep-green, sparingly viscid-puberulent or glabrate, prominently veined beneath; flowers dioecious, in dense stout spikes 5-15 cm. long and 7-10 mm. thick, these interrupted below; bracts ovate, ovate-oblong, or lanceolate, one third to two thirds as long as the calyx, acute, the nerves excurrent; sepals of the pistillate flowers somewhat united at the base, spatulate, 3—3.5 mm. long, rounded at the apex or obtuse, or the outer ones acute, often crenulate, glabrous, 1-nerved, the nerves sometimes shortly excurrent; sepals of the staminate flowers oblong or oblong-ovate, 3.5 mm. long, acute, subulatetipped, 1-nerved, green along the nerves, elsewhere thin and scarious, villous, viscid; stamens 5; style-branches 3; utricle oblong, acutish, slightly exceeding or shorter than the sepals, indehiscent; seed 1.3 mm. long, slightly longer than broad, nearly black, shining.
Type locality: Near the mouth of the Rio Grande, TamauKpas. Distribution: Along the coast from Galveston, Texas, to Tamaulipas.

Amaranthus annectens Blake, Jour. Bot. 53: 103. 1915
Stems branched, procumbent or ascending, stout, striate, glabrous, or sparsely glandularpuberulent about the nodes; petioles 4—9 mm. long, submarginate ; leafblades oblong or oblongspatulate, 1-1.8 cm. long, 3-4.5 mm. broad, truncate or retuse and cuspidate at the apex, cuneate at the base, more or less glutinous, strongly nerved beneath; flowers dioecious; staminate spikes flexuous, simple and naked above, leafy and sparsely branched at the base, 17 cm. long, 1.1 cm. thick, the sepals oval, acutish, green-carinate, 2.3 mm. long, sparsely glandular; stamens 5; pistillate spikes flexuous, simple or branched at the base, naked, 7-25 cm. long, 0.8-1 cm. thick, the bracts oval-ovate, acute, 1.3-1.7 mm. long, the sepals broadly obovateoblong or obovate-spatulate, 2.2-2.9 mm. long, retuse, cuspidate, 1-nerved, scarious-margined ; utricle ovoid-fusiform, subangulate, slightly inflated, fleshy-coriaceous, indehiscent, a third longer than the inner sepals; style-branches 3 or 2; seed globose-ovoid, 1.6-1.7 ram. long, lustrous, brownish-black.
Type locality: Seashore, Celestdn, Yucatan. Distribution: Known only from the type locality.

Amaranthus greggii, also known as Gregg's amaranth or Josiah amaranth, is a glabrous annual flowering plant native to Texas, Louisiana, and Mexico. The plant can grow up to 1 m (3 ft) in height. It is found in sand dunes and near sea beaches. The species name greggii honors Josiah Gregg (1806–1850), a merchant, explorer, naturalist, and author of the American Southwest and Northern Mexico.

Amaranthus greggii là loài thực vật có hoa thuộc họ Dền. Loài này được S.Watson mô tả khoa học đầu tiên năm 1877.