Amaranthus muricatus |
Amaranthus pumilus |
|
---|---|---|
African amaranth, muricate amaranth |
coast amaranth, sea-side amaranth, seabeach amaranth |
|
Habit | Plants annual or short-lived perennial, glabrous or slightly pubescent near tips. | Plants annual, glabrous. |
Stems | ascending or prostrate, much-branched from stout rootstock, 0.1–0.4 m. |
prostrate to ascending (often forming mats), red, much-branched, 0.1–0.4(–0.5) m, fleshy. |
Leaves | petiole to 1/2 as long as blade; blade linear to narrowly lanceolate, 1.5–8 × 0.2–0.5(–1) mm, base tapering, margins entire, plane to undulate, apex obtuse and often emarginate. |
clustered near tips of branches; petiole 5–10 mm; blade orbiculate, broadly ovate or obovate, 1–1.5 cm × 1–1.5 cm, fleshy, base broadly cuneate to tapering, margin entire, plane or slightly undulate, apex broadly rounded to obtuse, mucronate. |
Bracts | of pistillate flowers linear, 0.7–1.2 mm, 1/2–2/3 as long as tepals. |
of pistillate flowers ovate or elliptic, 1.2–2 mm, 1/2 as long as tepals. |
Inflorescences | terminal, compact pyramidal panicles and axillary glomerules, erect or reflexed, green, leafless at least distally. |
dense axillary glomerules, green. |
Staminate flowers | intermixed with pistillate or at tips of inflorescences; tepals 5; stamens 5. |
intermixed with pistillate; tepals 5; stamens 5. |
Pistillate flowers | tepals 5, narrowly oblanceolate, not clawed, equal, 1.5–2 mm, apex obtuse or subacute; style branches erect; stigmas 3. |
tepals 5, linear to narrowly oblanceolate, slightly unequal, 2.5–4 mm, margins entire, apex obtuse; style branches erect; stigmas 3. |
Seeds | black, lenticular, 1–1.2 mm diam., semiglossy. |
dark reddish brown, lenticular, 2.5 mm diam., glossy. |
Utricles | compressed, subglobose, 1.7–2 mm, ± equaling or slightly exceeding tepals, muricate, indehiscent. |
ovoid, 4–6 mm, exceeding tepals, fleshy, smooth or slightly rugose, longitudinally wrinkled on drying, indehiscent. |
Amaranthus muricatus |
Amaranthus pumilus |
|
Phenology | Flowering summer–fall. | Flowering summer–fall. |
Habitat | Waste places, on ballast | Maritime sand dunes, beaches, mostly on foredunes and at high tide level |
Elevation | 0 m (0 ft) | 0-10 m (0-0 ft) |
Distribution |
AL; s South America (Argentina, Paraguay, Uruguay) [Introduced in North America; introduced in s Europe, s Africa, Australia, and other regions] |
CT; DE; MA; MD; NC; NJ; NY; PA; RI; SC; VA |
Discussion | The vernacular name “African amaranth” is sometimes used for this species; it is a misnomer; the species is native to South America and naturalized in Africa. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Amaranthus pumilus is a globally and federally threatened species (Global Heritage Status Rank G2; National Heritage Status Rank N2) originally restricted to dunes and barrier island beaches along the Atlantic Ocean from southern Massachusetts to South Carolina. It has been eliminated from two-thirds of its former range, being last reported from Massachusetts in 1849, from Rhode Island in 1856, from New Jersey in 1913, and from Virginia in 1972 (S. Ramsey et al. 2000). As of fall 2003, extant populations are known only from Long Island, New York, Delaware, Maryland, North Carolina, and South Carolia. Many threats exist, including construction of sea walls and dune fencing, development, heavy recreational use, and off-road vehicle traffic. It is difficult to afford protection because of the dynamic nature of the habitat and the fugitive nature of the biology of the species. “Fugitive” refers to the fact that the species does not necessarily occur throughout its potential range at any given time (S. E. Clemants 1992). Amaranthus pumilus is in the Center for Plant Conservation’s National Collection of Endangered Plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 431. | FNA vol. 4, p. 430. |
Parent taxa | Amaranthaceae > Amaranthus > subg. Albersia | Amaranthaceae > Amaranthus > subg. Albersia |
Sibling taxa | ||
Synonyms | Euxolus muricatus | |
Name authority | (Moquin-Tandon) Hieronymus: Pl. Diaph. Fl. Argent., 227. (1882) | Rafinesque: Med. Repos., hexade 2, 5: 360. (1808) |
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