Euphorbia chaetocalyx |
Euphorbia cyparissias |
|||||
---|---|---|---|---|---|---|
bristlecup sandmat |
cypress spurge, euphorbe cypress, graveyard spurge |
|||||
Habit | Herbs, perennial, with woody, thickened taproot. | Herbs, perennial, with slender, spreading rootstock. | ||||
Stems | usually erect, rarely slightly decumbent, often densely clustered from top of woody crown, 3–15 cm, glabrous. |
erect or ascending, unbranched or branched, often with short axillary vegetative shoots with very narrow leaves, 10–50 cm, glabrous. |
||||
Leaves | opposite; stipules distinct, narrowly linear, usually entire, 0.5–1 mm, glabrous; petiole 0.5–1 mm, glabrous; blade ovate to lanceolate or oblong- or linear-lanceolate, 3–11 × 0.8–3(–5) mm, base slightly asymmetric, short-tapered, occasionally one side slightly rounded, margins entire, apex acute or short-acuminate, surfaces glabrous; only midvein conspicuous. |
petiole absent; blade linear to linear-ovate or linear-oblanceolate, 5–30 × 0.5–3 mm, base rounded to cuneate, margins entire, apex rounded to acute, surfaces glabrous; venation inconspicuous, only midvein prominent. |
||||
Involucre | campanulate to turbinate, 0.8–1.4 × 0.8–1 mm, glabrous; glands 4, yellow-brown to reddish, concave or convex, elliptic or oval, 0.2–0.4 × 0.4–0.6 mm; appendages absent or white, lanceolate-deltate to straplike, 0.2–1.1 × 0.2–0.9 mm, distal margin entire, crenate, or deeply cleft or divided. |
campanulate to slightly urceolate, 1.5–2 × 0.9–1.1 mm, glabrous; glands 4, crescent-shaped; 0.4–0.6 × 0.7–1.3 mm; horns convergent, 0.1–0.5 mm. |
||||
Staminate flowers | 25–35. |
15–25. |
||||
Pistillate flowers | ovary glabrous; styles 0.3–0.4 mm, 2-fid 1/2 length. |
ovary glabrous; styles 1–1.2 mm, 2-fid. |
||||
Capsules | depressed-ovoid to depressed-globose, 1.7–2.1 × 1.6–2.4 mm, glabrous; columella 1.2–1.8 mm. |
subglobose, 2.5–3 × 3–4 mm, slightly lobed; cocci rounded, granulate, glabrous; columella 1.9–2.1 mm. |
||||
Seeds | white, ovoid-pyramidal, prominently 4-angled in cross section, 1.6–2 × 1–1.2 mm, smooth to slightly wrinkled. |
blackish, ovoid-oblong, 1.8–2.5 × 1.4–1.7 mm, smooth; caruncle nipple-shaped or subreniform, 0.2–0.4 × 0.7–1.1 mm. |
||||
Cyathia | solitary at distal nodes; peduncle 0.8–1.3 mm. |
peduncle 0–0.5 mm. |
||||
Cyathial | arrangement: terminal pleiochasial branches 6–25, each 1–2-times 2-branched; pleiochasial bracts similar in shape to distal leaves except shorter and wider; dichasial bracts distinct, widely ovate, rhombic or reniform, base obtuse to truncate, margins entire, apex acute or obtuse, sometimes mucronulate; axillary cymose branches 0–15. |
|||||
Euphorbia chaetocalyx |
Euphorbia cyparissias |
|||||
Phenology | Flowering and fruiting spring–fall. | |||||
Habitat | Fields, roadsides, waste places. | |||||
Elevation | 0–1500 m. (0–4900 ft.) | |||||
Distribution |
AZ; NM; TX; n Mexico
|
AR; CA; CO; CT; DC; DE; GA; IA; ID; IL; IN; KY; MA; MD; ME; MI; MN; MO; MT; NC; NE; NH; NJ; NY; OH; OR; PA; RI; SC; TN; UT; VA; VT; WA; WI; WV; WY; BC; MB; NB; NF; NS; ON; PE; QC; SK; Europe [Introduced in North America]
|
||||
Discussion | Varieties 2 (2 in the flora). Euphorbia chaetocalyx is similar to E. fendleri but can generally be distinguished from that species by its narrow, acute leaves and ± erect stems. Some authors have used the presence or absence and shape of the involucral gland appendages to help separate E. chaetocalyx from E. fendleri, but those characters appear highly variable and of little taxonomic utility. Some individuals from western Texas (Culberson and El Paso counties) and southern New Mexico appear intermediate with E. fendleri. The specific epithet of E. chaetocalyx refers to the bristly perianthlike segments that subtend the ovary, but these structures are found intermittently in both E. chaetocalyx and E. fendleri. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|||||
Key |
|
|||||
Source | FNA vol. 12, p. 263. | FNA vol. 12, p. 301. | ||||
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > subg. Esula | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | E. fendleri var. chaetocalyx, Chamaesyce chaetocalyx | Galarhoeus cyparissias, Tithymalus cyparissias | ||||
Name authority | (Boissier) Tidestrom: Proc. Biol. Soc. Wash. 48: 40. (1935) | Linnaeus: Sp. Pl. 1: 461. (1753) | ||||
Web links |
|