Atriplex coulteri |
Atriplex covillei |
|
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Coulter's orach, Coulter's orache, Coulter's saltbush |
Coville's orach |
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Habit | Herbs, perennial, sometimes flowering as an annual, spreading 0.7–10 dm, slightly woody at base. | Herbs, spreading, 1–4(–5) dm and as broad. |
Stems | frequently tinged with red, much branched, sparsely scurfy. |
terete, sparsely scurfy when young. |
Leaves | many, sessile or short petiolate; blade obovate, oblong, oblanceolate, or elliptic, (5–)7–20 × 1–3(–5) mm, base cuneate, margin entire, apex acute. |
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 glomerules in distal axils and short terminal spikes. |
in sessile glomerules in distal axils, often mixed with pistillate ones, staminate calyx deeply 5-cleft; lobes obtuse, not appendaged. |
Pistillate flowers | in small axillary clusters. |
with calyx of (1–)3(–5) hyaline sepals. |
Seeds | brown, 1.3–1.5 mm. |
dark reddish brown, 1–1.5 mm. |
Fruiting | bracteoles sessile or subsessile, broadly obovate, 2–3 mm and as broad or about as broad, united 1/2 of length, margin free, deeply and sharply dentate, narrowed at summit, faces smooth or sometimes tuberculate. |
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 coulteri |
Atriplex covillei |
|
Phenology | Flowering spring–fall. | Flowering summer–fall. |
Habitat | Somewhat alkaline or clay low places, valley grasslands, coastal sage scrub, coastal slopes | Mixed saltbush-greasewood, rabbitbrush, warm desert shrub, and salt grass communities in saline substrates |
Elevation | 0-500 m (0-1600 ft) | 800-1700 m (2600-5600 ft) |
Distribution |
CA
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CA; NV; OR |
Discussion | Of conservation concern. Atriplex coulteri is closely allied to the geographically disjunct A. fruticulosa, from which it is said to differ in the compressed, small (2.5–3 mm) versus thickened and larger (3–5 mm) bracts. Specimens of A. fruticulosa, including the type, examined by me have bracteoles compressed-thickened, but hardly “globoid” as stated in the key to the species by H. M. Hall and F. E. Clements (1923). Additional specimens borrowed from California might clarify the situation; otherwise the two species are sufficiently close as to be treated as a single entity. (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. 363. | FNA vol. 4. |
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae | Chenopodiaceae > Atriplex > subg. Obione > sect. Covilleiae |
Sibling taxa | ||
Synonyms | Obione coulteri | Endolepis covillei |
Name authority | (Moquin-Tandon) D. Dietrich: Syn. Pl. 5: 537. (1852) | (Standley) J. F. Macbride: Contr. Gray Herb. 53: 11. (1918) |
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