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seas hore orach

Coville's orach

Habit Herbs, annual or perennial, sprawling to erect, often suffrutescent at the base, much branched and clump-forming, 3–10 dm. Herbs, spreading, 1–4(–5) dm and as broad.
Stems

obtusely angled, finely scurfy when young.

terete, sparsely scurfy when young.

Leaves

sessile or short petiolate;

blade paler abaxially, oblong or rhombic-ovate to broadly obovate or narrowly oblong or narrowly elliptic, 10–30 × (1–)3–15 mm, thin, base rounded to cuneate, margin repand-dentate or sinuate-dentate to undulate or distal ones or all of them entire, apex rounded to acute, mucronate, densely white scurfy abaxially, grayish green and usually glabrate adaxially.

petiole to 1/2 as long as blade (becoming subsessile distally);

blade green or finally stramineous, (10–)20–50 × 6–30 mm, firm, base abruptly acute to narrowly cuneate, apex acute to attenuate, sparsely scurfy.

Staminate flowers

in short, dense, naked terminal spikes or panicles;

calyx 5-cleft, lobes green keeled.

in sessile glomerules in distal axils, often mixed with pistillate ones, staminate calyx deeply 5-cleft;

lobes obtuse, not appendaged.

Pistillate flowers

fascicled in axils.

with calyx of (1–)3(–5) hyaline sepals.

Seeds

brown, 1–1.5 mm.

dark reddish brown, 1–1.5 mm.

Fruiting

bracteoles sessile or with stipes to 0.5 mm, broadly cuneate-orbiculate, compressed, (2–) 2.5–4.5 × (1.5–)2.6–5 mm, usually as broad as or broader than long, much thickened at maturity, united only at truncate or broadly cuneate base, margin deeply and acutely dentate, faces with 2, sometimes swollen, dentate crests or covered with irregular, conic-acute, corky tubercles, seldom smooth.

bracteoles sessile or stipitate, 6–12 × 4–7 mm, margin mostly 3-lobed, with elongate terminal lobe triangular to lanceolate, 2 short rounded lobes at base or sides merely rounded at base, united to beyond middle.

Atriplex pentandra

Atriplex covillei

Phenology Flowering summer–fall. Flowering summer–fall.
Habitat Sandy seashores, coastal salt marshes Mixed saltbush-greasewood, rabbitbrush, warm desert shrub, and salt grass communities in saline substrates
Elevation 0-50 m (0-200 ft) 800-1700 m (2600-5600 ft)
Distribution
from FNA
AL; CT; FL; GA; LA; MA; MS; NC; SC; TX; West Indies; South America (Venezuela and Colombia to Peru)
from FNA
CA; NV; OR
Discussion

D. S. Correll and M. C. Johnston (1970), treated both Atriplex texana and A. wardii at the specific level. The diagnostic features used to distinguish them, dentate versus entire leaf blades and smooth versus tuberculate faces of fruiting bracteoles, fail singly and in combination. Both taxa were regarded by H. M. Hall and F. E. Clements (1923) as variants of typical A. pentandra, and this worker tentatively agrees with those authors’ conclusions. Specimens from Galveston, Texas—the type locality of A. wardii—are apparently intermediate with A. mucronata (see below) and form the basis on which A. wardii was founded. Some of those specimens have been annotated by me and others as A. mucronata. The plants have entire leaves more closely matching those of A. mucronata, but the small fruiting bracteoles, though usually lacking tubercles on the faces, are of similar proportions to those of typical A. pentandra. Atriplex pentandra and A. mucronata are certainly very closely allied.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Endolepis covillei was treated within the synonymy of Atriplex phyllostegia (Torrey) S. Watson by H. M. Hall and F. E. Clements (1923).

H. C. Stutz et al. (1993) placed Atriplex covillei within Endolepis, based in large part on the presence of a perianth subtending the pistil within the fruiting bracteoles and on the lack of Kranz anatomy in the leaves. The pattern of venation is, nevertheless, very similar to that in species with Kranz anatomy. The presence of perianth scales in the pistillate flowers of A. covillei has been regarded as evidence of relationship with A. suckleyi. Despite placement of these taxa within Endolepis by Stutz et al. Atriplex covillei is possibly more closely allied to the morphologically similar and partially sympatric A. phyllostegia than it is to strongly dissimilar and the distantly disjunct A. suckleyi. Stutz and his associates placed great emphasis on the presence of reduced perianth segments subtending the pistil within the fruiting bracteoles of A. covillei. Calyces per se, otherwise known only in A. suckleyi and A. pleiantha, probably have arisen independently. Their presence does not necessarily indicate a close relationship. Stutz et al. pointed to other differences aside from the calyx of the pistillate flowers, and it is apparent that the two entities can stand as distinct species. To segregate A. covillei within a separate genus and to ally it with a species to which its relationships are obscure at best, stretches logic beyond reason.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 4, p. 362. FNA vol. 4.
Parent taxa Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae Chenopodiaceae > Atriplex > subg. Obione > sect. Covilleiae
Sibling taxa
A. acanthocarpa, A. amnicola, A. argentea, A. californica, A. canescens, A. confertifolia, A. cordulata, A. coronata, A. corrugata, A. coulteri, A. covillei, A. dioica, A. elegans, A. fruticulosa, A. gardneri, A. garrettii, A. glabriuscula, A. gmelinii, A. graciliflora, A. heterosperma, A. holocarpa, A. hortensis, A. hymenelytra, A. joaquiniana, A. klebergorum, A. laciniata, A. lentiformis, A. leucophylla, A. lindleyi, A. linearis, A. littoralis, A. matamorensis, A. mucronata, A. nudicaulis, A. nummularia, A. oblongifolia, A. obovata, A. pacifica, A. parishii, A. parryi, A. patula, A. phyllostegia, A. pleiantha, A. polycarpa, A. powellii, A. prostrata, A. pusilla, A. rosea, A. saccaria, A. semibaccata, A. serenana, A. spinifera, A. suberecta, A. suckleyi, A. tatarica, A. torreyi, A. truncata, A. tularensis, A. watsonii, A. wolfii, A. wrightii
A. acanthocarpa, A. amnicola, A. argentea, A. californica, A. canescens, A. confertifolia, A. cordulata, A. coronata, A. corrugata, A. coulteri, A. dioica, A. elegans, A. fruticulosa, A. gardneri, A. garrettii, A. glabriuscula, A. gmelinii, A. graciliflora, A. heterosperma, A. holocarpa, A. hortensis, A. hymenelytra, A. joaquiniana, A. klebergorum, A. laciniata, A. lentiformis, A. leucophylla, A. lindleyi, A. linearis, A. littoralis, A. matamorensis, A. mucronata, A. nudicaulis, A. nummularia, A. oblongifolia, A. obovata, A. pacifica, A. parishii, A. parryi, A. patula, A. pentandra, A. phyllostegia, A. pleiantha, A. polycarpa, A. powellii, A. prostrata, A. pusilla, A. rosea, A. saccaria, A. semibaccata, A. serenana, A. spinifera, A. suberecta, A. suckleyi, A. tatarica, A. torreyi, A. truncata, A. tularensis, A. watsonii, A. wolfii, A. wrightii
Synonyms Axyris pentandra, A. texana, A. wardii Endolepis covillei
Name authority (Jacquin) Standley: in N. L. Britton et al., N. Amer. Fl. 21: 54. (1916) (Standley) J. F. Macbride: Contr. Gray Herb. 53: 11. (1918)
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