Euphorbia parryi |
Euphorbia lurida |
|
---|---|---|
dune spurge, Parry's sandmat, Parry's spurge |
woodland spurge |
|
Habit | Herbs, annual, with taproot. | Herbs, perennial, with thick rootstock. |
Stems | usually prostrate, rarely ascending-erect, 5–70(–85) cm, glabrous. |
erect or ascending, unbranched, sometimes sinuous, 5–30 cm, glabrous or sparsely to densely puberulent. |
Leaves | opposite; stipules distinct, linear-subulate, usually lacerate and divided into 2 or more slender segments, rarely entire, 0.6–1.4 mm, glabrous; petiole 1–2.5 mm, glabrous; blade linear to narrowly oblong, (5–)10–25(–30) × 2–5 mm, base usually symmetric, sometimes slightly asymmetric, attenuate, margins entire, occasionally ± revolute, apex acute to obtuse, mucronulate, surfaces glabrous; only midvein conspicuous. |
petiole 0–1 mm; blade oblanceolate to obovate, 8–20 mm × 3–7 mm, base truncate or cuneate, margins entire, apex obtuse to rounded, minutely mucronate, surfaces puberulent or glabrous; venation inconspicuous, only midvein prominent. |
Involucre | broadly cupuliform-campanulate, 1.2–1.7 × 1.4–1.8 mm, glabrous; glands 4, reddish pink to greenish yellow, deeply concave, elliptic to oblong, 0.2–0.3 × 0.3–0.5 mm; appendages white, elliptic to oblong, usually forming narrow margin around gland, sometimes rudimentary, 0.2–0.6 × 0.3–0.7(–1.1) mm, distal margin entire. |
cupulate, 2–2.2 × 1.3–1.8 mm, glabrous; glands 4, oblong to broadly ovate, usually truncate, 0.5–0.8 × 1–1.6 mm, margins irregularly crenate to strongly dentate; horns absent or usually divergent or straight, 0.1–0.3 mm, usually slightly longer than, occasionally equaling, teeth on gland margin. |
Staminate flowers | 40–55. |
10–20. |
Pistillate flowers | ovary glabrous; styles 0.5–0.7 mm, 2-fid nearly entire length. |
ovary glabrous or puberulent; styles 0.7–1 mm, 2-fid. |
Capsules | ovoid-globose, 2–2.3 × 1.5–2.5 mm, glabrous; columella 1.4–2 mm. |
ovoid, 3.5–4 × 4–4.5 mm, 3-lobed; cocci rounded, smooth to slightly rugose, glabrous; columella 3.2–3.5 mm. |
Seeds | mottled brown and white because of irregularly loose and tight outer covering, broadly ovoid, rounded-angular in cross section, 1.4–1.8 × 0.8–1 mm, smooth or only inconspicuously roughened. |
gray to dark gray, truncate-oblong to truncate-ovoid, 2.8–3 × 1.7–2 mm, irregularly pitted; caruncle conic, 0.6 × 0.7 mm. |
Cyathia | solitary or in small clusters on short axillary branches at distal nodes; peduncle 1–5 mm. |
peduncle 0.3–0.9 mm. |
Cyathial | arrangement: terminal pleiochasial branches 3–5, each 1–4 times 2-branched; pleiochasial bracts ovate to broadly ovate or oblanceolate, wider than distal leaves; dichasial bracts distinct, rounded, oblanceolate, or subreniform, base cuneate or obtuse, margins entire, apex obtuse, slightly mucronate; axillary cymose branches 0–4. |
|
Euphorbia parryi |
Euphorbia lurida |
|
Phenology | Flowering and fruiting spring–fall. | Flowering and fruiting spring–summer. |
Habitat | Sand dunes, other sandy habitats. | Open pine-oak forests, dry slopes and canyons. |
Elevation | 200–2200 m. (700–7200 ft.) | 1300–2800 m. (4300–9200 ft.) |
Distribution |
AZ; CA; CO; NM; NV; TX; UT; Mexico (Chihuahua)
|
AZ; CA; NM; NV; UT; Mexico (Baja California)
|
Discussion | Euphorbia parryi is similar to E. missurica, differing only by the generally narrow involucral gland appendages and prostrate habit in E. parryi as opposed to the conspicuous involucral gland appendages and ascending-erect habit in E. missurica. Euphorbia parryi has sometimes been considered the western race of E. missurica (D. S. Correll and M. C. Johnston 1970). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia lurida has been treated as a complex of several taxa in the past, but only a single, broadly-defined species is recognized here. This species is variable in both the pubescence and shape of the bracts subtending the cyathia and also in the degree of crenation of the gland margin. In the northern part of its range, E. lurida appears to intergrade with E. brachycera, and it can be difficult to distinguish these two species in northern Arizona and New Mexico. A report of the species from Sonora, Mexico, based on a single immature collection (V. W. Steinmann and R. S. Felger 1997) has not been verified. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 281. | FNA vol. 12, p. 305. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > subg. Esula |
Sibling taxa | ||
Synonyms | Chamaesyce longeramosa, C. parryi, E. longeramosa | E. palmeri, E. palmeri var. subpubens, E. subpubens, Tithymalus luridus, T. palmeri, T. subpubens |
Name authority | Engelmann: Amer. Naturalist 9: 350. (1875) | Engelmann: in J. C. Ives, Rep. Colorado R. 4: 26. (1861) |
Web links |