Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Euphorbia polycarpa

Euphorbia sect. Anisophyllum

smallseed sandmat
Habit Herbs, rarely subshrubs or shrubs, annual or perennial, with taproot or thickened rootstock.
Stems

usually prostrate, sometimes erect, ascending, reclining, or decumbent, branched [unbranched], terete or flattened, glabrous or hairy.
Leaves

opposite (rarely whorled in E. fendleri);

stipules present, deciduous, (sometimes appearing absent in E. acuta), interpetiolar (at base of petiole in E. acuta);

petiole present [absent], glabrous or hairy;

blade monomorphic, base usually asymmetric, rarely symmetric, margins entire or variously toothed, surfaces glabrous or hairy;

venation usually palmate or palmate at base and pinnate distally, sometimes pinnate, often only midvein conspicuous.
Involucre

± actinomorphic, not spurred;

glands (2–)4, slightly concave, flat, or slightly convex;

appendages petaloid or absent.
Staminate flowers

(0–)1–80.
Pistillate flowers

ovary glabrous or hairy;

styles distinct or connate basally, unbranched or 2-fid.
Seeds

caruncle absent (except for a carunclelike structure in E. carunculata).
Euphorbia

polycarpa is a highly variable species distributed throughout the Baja California peninsula, eastern Sonora, and the arid southwestern United States from southwestern Arizona to southern Nevada and central California.

l

.

c

.

Wheeler

(1941) divided the species into seven varieties, the majority of which occur in Baja California Sur.

He

reported two of these for the United States: var. hirtella and var. polycarpa.

Variety

hirtella, as the name suggests, was applied to hairy plants.

However

, it is here treated as a synonym of var. polycarpa, because variation in pubescence shows no geographic segregation and ranges along a continuum from glabrous or sparsely to densely hairy, and because glabrous and hairy branches can occur on the same individual.

Cyathial

arrangement: terminal or axillary, solitary or in cymose clusters or capitate glomerules;

bracts absent (except for small, bractlike leaves in capitate glomerules).

Euphorbia polycarpa

Euphorbia sect. Anisophyllum
Distribution
from FNA
AZ; CA; NV; nw Mexico
[WildflowerSearch map]
[BONAP county map]
North America; Mexico; Central America; South America; West Indies; Bermuda; Eurasia; Africa; Atlantic Islands; Indian Ocean Islands; Pacific Islands; Australia
Discussion

Varieties 5 (1 in the flora).

Some of the varieties occurring in Mexico are highly divergent and appear to be sufficiently distinct to merit recognition as species. However, within the flora area, Euphorbia polycarpa is relatively uniform, and the only noteworthy variation involves the size of the involucral gland appendages. In the portion of the California Floristic Province occupied by E. polycarpa (Los Angeles, Orange, western Riverside, western San Diego, and Ventura counties) the appendages are conspicuously larger than those of plants throughout the remainder of its range in the southwestern United States (0.4–1.2 versus 0.1–0.3 mm). Large-appendaged plants are also common in Baja California and correspond well with the type collection. The taxonomic significance of this variation is not clear at this time, and the small-appendaged plants may merit segregation as an infraspecific taxon. However, no formal changes are proposed, awaiting a comprehensive review of the species throughout its range.

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

Species ca. 300 (69 in the flora).

In the key and descriptions that follow, for species with mostly prostrate stems, the side of the stem toward the ground is called the lower side and the opposite side is call the upper side.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Key
1. Ovaries and capsules ± hairy.
→ 2
2. Cyathia in capitate glomerules (with reduced, bractlike leaves subtending cyathia).
→ 3
3. Stipules distinct when young, connate into deltate scales when older, often with dark glands along margins or at base; styles 0.6–0.9 mm; seeds plumply ovoid, 0.7–0.8 mm wide, dark reddish brown to almost black; s Florida.
E. lasiocarpa
3. Stipules distinct or connate only at base, deltate, subulate, or linear- or filiform-subulate, without dark glands along margins or at base; styles 0.1–0.6 mm; seeds narrowly ovoid or ovoid-oblong, 0.5–0.7 mm wide, not dark reddish brown to almost black; widespread, including s Florida.
→ 4
4. Glomerules of cyathia terminal and axillary, axillary glomerules sessile or at tips of elongated, leafless stalks.
E. hirta
4. Glomerules of cyathia terminal, on main stems or short, leafy, axillary branches, with reduced, bractlike leaves subtending cyathia.
→ 5
5. Stems glabrous, strigillose, or pilose; involucre 0.8–1.6 × 0.7–1.3 mm, appendages 0.2–1.1 × 0.5–1.7 mm; styles 0.4–0.6 mm; capsules pilose; seeds 0.9–1.5 mm.
E. capitellata
5. Stems usually both strigillose and hirsute; involucre 0.5–0.7 × 0.4–0.6 mm, appendages 0.1–0.2 × 0.1–0.3 mm; styles 0.1–0.3 mm; capsules strigillose; seeds 0.7–0.9(–1.1) mm.
E. ophthalmica
2. Cyathia solitary or in small, cymose clusters at distal nodes, on congested, axillary branches, or at branch tips.
→ 6
6. Involucral gland appendages unequal.
→ 7
7. Seeds 3-angled to almost round in cross section, with 4–5 rounded, transverse ridges encircling seed; Arizona, California.
E. pediculifera
7. Seeds conspicuously 4-angled in cross section, variously grooved or ridged, but not with 4–5 rounded, transverse ridges encircling seed; Florida, Louisiana (E. conferta, E. pergamena, and E. thymifolia) or sw United States (E. indivisa).
→ 8
8. Styles 0.8–1.3 mm, usually unbranched, rarely 2-fid at apex; sw United States from Arizona to Texas.
E. indivisa
8. Styles 0.4–1 mm, 2-fid; Florida, Louisiana.
→ 9
9. Stems pilose.
E. conferta
9. Stems strigose to sericeous or strigose-tomentulose.
→ 10
10. Capsules well exserted from involucre at maturity; seeds with 3 or 4 transverse sulci alternating with low transverse ridges.
E. pergamena
10. Capsules scarcely exserted from involucre, base often remaining inside the involucre and splitting one side of it during maturity; seeds with 4 low transverse ridges, but not sulcate.
E. thymifolia
6. Involucral gland appendages ± equal in size or rudimentary to absent.
→ 11
11. Leaf margins toothed, at least toward apex.
→ 12
12. Styles unbranched.
→ 13
13. Stems strigillose; seeds broadly ovoid, 1.2–1.4 × 1–1.1 mm, with 2 well-defined transverse ridges.
E. rayturneri
13. Stems pilose to lanate; seeds narrowly oblong-ovoid to ellipsoid, 1–1.5 × 0.5–0.6 mm, almost smooth, rugulose, dimpled, or with short and irregularly interrupted furrows (seeds appearing partially and irregularly few-ridged).
E. stictospora
12. Styles 2-fid.
→ 14
14. Capsules with pubescence concentrated along keels or toward base, often glabrous between keels.
→ 15
15. Petioles, leaf blade abaxial surfaces, ovaries, and capsules glabrous or sparsely sericeous, pilose, or villous; seeds reddish brown to orange or gray-pink, almost smooth or with faint transverse ridges; s Florida.
E. mendezii
15. Petioles, leaf blade abaxial surfaces, ovaries, and capsules crisped-villous to glabrate; seeds white but with barely concealed brown surface beneath, with sharp transverse ridges; widespread, including s Florida.
E. prostrata
14. Capsules ± evenly hairy or pubescence at least not concentrated only along keels and base, not glabrous between keels.
→ 16
16. Capsules pilose to villous.
→ 17
17. Involucral gland appendages not puberulent-ciliate along margins; capsule 1.4–1.9 × 1.5–2 mm; seeds ovoid to narrowly ovoid, 1–1.4 × 0.6–0.9 mm; California.
E. serpillifolia
17. Involucral gland appendages often puberulent-ciliate along margins; capsule 1.5–1.9 × 1.3–1.7 mm; seeds narrowly pyramidal-ovoid, 1.1–1.3 × 0.4–0.6 mm; Texas.
E. velleriflora
16. Capsules strigose to sericeous.
→ 18
18. Capsules scarcely exserted from involucre, base often remaining inside involucre and splitting one side of it during maturity.
E. thymifolia
18. Capsules well exserted from involucre at maturity.
→ 19
19. Stems rooting at nodes; styles 0.5–0.8 mm; seeds bluntly angled, smooth or papillate.
E. humistrata
19. Stems not rooting at nodes; styles 0.3–0.4 mm; seeds sharply angled, with 3–4 low transverse ridges.
E. maculata
11. Leaf margins entire (rarely sparsely serrulate in E. garberi and E. laredana).
→ 20
20. Capsules with pubescence concentrated along keels or toward base, often glabrous or less hairy between keels.
E. laredana
20. Capsules ± evenly hairy or pubescence at least not concentrated only along keels and base, not glabrous between keels.
→ 21
21. Involucral gland appendages divided into 3–8 triangular to subulate segments.
→ 22
22. Shrubs; stems ascending, puberulent to shortly hirsute; stipules 0.3–0.5 mm; seeds 1.4–1.5 mm.
E. jaegeri
22. Annual herbs; stems prostrate, villous, hairs glandular-glistening; stipules rudimentary to 0.2 mm; seeds 0.8–1 mm.
E. setiloba
21. Involucral gland appendages entire, toothed, or absent.
→ 23
23. Proximal leaf blades ovate to ovate-elliptic, distal ones linear to elliptic-linear, more than 6 times as long as wide.
E. angusta
23. Leaf blades not linear (rarely linear in E. pediculifera), less than 3 times as long as wide.
→ 24
24. Stems glabrous or sparsely hairy.
E. deltoidea
24. Stems conspicuously and densely hairy.
→ 25
25. Stems with appressed hairs.
→ 26
26. Leaf blade apices long-acuminate and spinulose; seeds 2.2–2.6 mm.
E. acuta
26. Leaf blade apices acute to obtuse or rounded; seeds 0.8–1.8(–2) mm.
→ 27
27. Largest leaf blades usually more than 15 mm; seeds 3-angled to almost round in cross section, with 4–5 rounded, transverse ridges encircling seed.
E. pediculifera
27. Largest leaf blades less than 15 mm; seeds 3- or 4-angled in cross section, without 4–5 rounded, transverse ridges encircling seed.
→ 28
28. Involucral glands deep red, purple, or purple-black.
→ 29
29. Involucral gland appendages absent or forming narrow rim around distal margin of gland, 0–0.1 × 0–0.6 mm; seeds ovoid, 1–1.4 × 0.6–0.8 mm; Texas.
E. cinerascens
29. Involucral gland appendages oblong to flabellate, 0.4–0.7(–1) × 0.7–1.2 mm; seeds narrowly oblong, 1–1.2 × 0.4–0.6 mm; Arizona, California.
E. melanadenia
28. Involucral glands green to yellow-green or brown.
→ 30
30. Stipules filiform, 0.8–1.3 mm; involucres 2–2.5 × 2.2–2.6 mm; styles 0.8–1.2 mm; capsules 1.9–2.3 × 2–2.4 mm; seeds whitish, 1.5–1.8(–2) × 0.6–0.9 mm; c, s United States but not Florida.
E. lata
30. Stipules triangular or triangular-subulate, 0.2–0.7 mm; involucres 0.6–1 × 0.5–1.3 mm; styles 0.3–0.7 mm; capsules 1.1–1.6 × 1.3–2.2 mm; seeds gray to reddish brown, 0.8–1.2 × 0.5–0.8 mm; s Florida.
→ 31
31. Stems wiry, less than 1 mm diam., 5–20 cm; leaf blades deltate, 2–5(–7) × 1–4.5 mm.
E. deltoidea
31. Stems not wiry, 1–3 mm diam., 15–50 cm; leaf blades ovate to oblong-elliptic, 4–9(–15) × 3–6 mm.
E. garberi
25. Stems with spreading to erect hairs.
→ 32
32. Stems and leaves with glistening hairs; stipules (0–)0.1 mm.
E. arizonica
32. Stems and leaves without glistening hairs; stipules 0.2–1.6 mm.
→ 33
33. Involucres 0.4–0.6 × 0.5–0.9 mm, glands 0.1 × 0.1–0.2 mm, appendages absent.
E. micromera
33. Involucres 0.6–2.5 × 0.5–2.4 mm, glands 0.1–0.6 × 0.2–0.9 mm, appendages usually present (absent or forming narrow rim in some specimens of E. deltoidea; sometimes forming narrow rim in E. polycarpa).
→ 34
34. Involucral gland appendages ciliate-puberulent adaxially; perennial herbs.
E. vallis-mortae
34. Involucral gland appendages not ciliate-puberulent adaxially; annual or perennial herbs.
→ 35
35. Seeds 1.1–1.7 × 0.8–1.3 mm.
E. ocellata
35. Seeds 0.8–1.2 × 0.5–0.8 mm.
→ 36
36. Stems prostrate to ascending, mat-forming; sw United States.
E. polycarpa
36. Stems ascending to erect, not mat-forming; s Florida.
→ 37
37. Stems and leaves villous or villous-hirsute; stems ascending to erect, wiry, less than 1 mm diam., 5–20 cm; leaf blades deltate, 2–4.5 × 2–4.5 mm.
E. deltoidea
37. Stems and leaves canescent; stems ascending, not wiry, 1–3 mm diam., 15–50 cm; leaf blades ovate to oblong-elliptic, 4–9(–15) × 3–6 mm.
E. garberi
1. Ovaries and capsules glabrous.
→ 38
38. Leaf blades linear, 5 times or more as long as wide, bases symmetric or subsymmetric (sometimes slightly asymmetric in E. parryi).
→ 39
39. Leaf blade margins serrulate.
E. florida
39. Leaf blade margins entire.
→ 40
40. Stipules entire; seeds 0.9–1.4 mm, 4-angled in cross section.
→ 41
41. Stipules 0.3–0.5 mm; involucres 0.4–0.5 mm, glands yellow to pink; styles 2-fid; capsules 1.1–1.4 × 1.1–1.4 mm; s Arizona.
E. gracillima
41. Stipules 0.5–0.9 mm; involucres 0.7–0.9 mm, glands pink to dark purple; styles unbranched; capsules 1.5–1.8 × 1.6–1.8 mm; sw United States, including s Arizona.
E. revoluta
40. Stipules usually deeply and irregularly fringed, lobed, or lacerate and divided into slender segments, rarely entire; seeds 1.4–2 mm, bluntly 3-angled or rounded-angular in cross section.
→ 42
42. Stems erect or ascending; involucral gland appendages 0.4–2.5 × 1.1–1.7 mm.
E. missurica
42. Stems usually prostrate, rarely ascending-erect; involucral gland appendages 0.2–0.6 × 0.3–0.7(–1.1) mm.
E. parryi
38. Leaf blades not linear, 4 times or less as long as wide, bases usually asymmetric, rarely subsymmetric to symmetric.
→ 43
43. Styles unbranched.
→ 44
44. Annual herbs with slender taproots; leaf blade margins serrulate to denticulate; styles filiform, 1.8–2.6 mm; California.
E. hooveri
44. Perennial herbs with thickened taproots; leaf blade margins entire; styles thickened-clavate, 0.3–0.5 mm; Texas.
→ 45
45. Petioles 0–0.2(–0.3) mm; leaf blade bases cordate to auriculate; involucral gland appendages 0.1–0.2(–0.5) × 0.4–0.8 mm, entire or dentate-crenate.
E. astyla
45. Petioles 0.3–0.9 mm; leaf blade bases rounded to truncate; involucral gland appendages 0.3–0.6 × 0.8–1.2 mm, usually deeply dissected into 4–5 acuminate lobes, rarely entire or crenate.
E. jejuna
43. Styles 2-fid at least toward apex.
→ 46
46. Cyathia in capitate glomerules (with reduced, bractlike leaves subtending cyathia).
→ 47
47. Stipules distinct, filiform or divided into subulate-filiform segments; leaf blades ovate to narrowly ovate, often with red spot in center, 4–19 × 2–8 mm; stems and leaves glabrous, strigillose or pilose.
E. capitellata
47. Stipules connate, deltate, entire; leaf blades obliquely oblong-oblanceolate, 10–35 × 7–15 mm; stems and leaves glabrous.
E. hypericifolia
46. Cyathia solitary or in small cymose clusters at distal nodes or on congested, axillary branches.
→ 48
48. Leaf blade margins toothed (at least toward apex or on majority of leaves).
→ 49
49. Seeds with prominent transverse ridges that interrupt abaxial keel.
→ 50
50. Stems shortly pilose or puberulent proximally (often glabrous distally); capsules 1.3–1.5 × 1.1–1.5 mm.
E. abramsiana
50. Stems glabrous; capsules 1.3–1.9 × 1.6–2 mm.
E. glyptosperma
49. Seeds without prominent transverse ridges, or if present, not interrupting abaxial keel.
→ 51
51. Largest leaf blades more than 20 mm.
→ 52
52. Seeds 1.9–2.3 × 1.3–1.4 mm; stems and leaves glabrous.
E. trachysperma
52. Seeds 1–1.6 × 0.5–1.1 mm; stems and leaves glabrous or hairy.
→ 53
53. Stems sparsely to densely pilose or pilose-crinkled proximally, usually glabrous distally; leaf blades glabrous or sparsely pilose toward base (abaxially), glabrous (adaxially); seeds with prominent transverse ridges or coarsely and inconspicuously pitted-reticulate.
E. hyssopifolia
53. Stems sparsely to moderately pilose to villous or with short, incurved hairs, pubescence often concentrated at nodes and distally (hairs occasionally in 2 bands along opposite sides of stem); leaf blades usually sparsely to moderately pilose, especially toward base, sometimes glabrous; seeds finely and irregularly wrinkled or with indistinct shallow, rounded cross ridges.
E. nutans
51. Largest leaf blades less than 20 mm.
→ 54
54. Leaf blade surfaces papillate; cocci of capsule often elongated and terminating in empty portion.
E. villifera
54. Leaf blade surfaces not papillate; cocci of capsule not elongated or terminating in empty portion.
→ 55
55. Stem and leaves glabrous.
→ 56
56. Seeds pyramidal to oblong-ovoid, weakly 4-angled in cross section, 0.9–1 × 0.7 mm, reddish brown to brown, minutely beaded, with broad, rounded, transverse ridges; s coastal Louisiana and adjacent Texas.
E. meganaesos
56. Seeds ovoid to narrowly ovoid, 4-angled in cross section, 1–1.4 × 0.6–0.9 mm, pink, light brown or grayish, smooth to dimpled or rugose, or with faint transverse ridges; widespread, but not coastal Louisiana and adjacent Texas.
E. serpillifolia
55. Stem and leaves usually hairy, rarely glabrate.
→ 57
57. Leaf blade margins serrate to serrulate, usually with conspicuous teeth at base; capsules 2–2.6 × 3.2–3.7 mm; seeds 1.5–1.8 × 1.1–1.3(–1.5) mm.
E. serrula
57. Leaf blade margins usually entire in proximal 1/2 and serrulate in distal 1/2 (rarely some leaves with margins nearly entire in E. vermiculata; rarely some leaves serrulate nearly to base in E. serpillifolia); capsules 1.4–1.9 × 1.5–2.1 mm; seeds 1–1.4 × 0.6–0.9 mm.
→ 58
58. Stems prostrate to ascending, often mat-forming; cyathial glands yellow to pink; seeds smooth to dimpled or rugose, or with faint transverse ridges; California.
E. serpillifolia
58. Stems prostrate to ascending or erect, not mat-forming; cyathial glands red to reddish green; seeds rugulose and sometime also with low transverse ridges; Arizona, New Mexico, ne United States, Canada.
E. vermiculata
48. Leaf blade margins entire (occasionally toothed in E. blodgettii; rarely sparsely serrate in E. porteriana).
→ 59
59. Stipules (at least those of upper side of stem) connate, forming deltate, ligulate, or ovate scale.
→ 60
60. Subshrubs or shrubs; stems erect to ascending; leaf blade bases slightly asymmetric.
E. mesembrianthemifolia
60. Herbs; stems prostrate to decumbent and often rooting at nodes; leaf blade bases asymmetric.
→ 61
61. Perennials; involucral glands 0.2–0.5 × (0.2–)0.3–0.8 mm, appendages 0.3–1 × 0.6–1.3 mm; leaf blades often with red blotch in center.
E. albomarginata
61. Annuals, rarely short-lived perennials; involucral glands 0.1 × 0.1–0.3 mm, appendages 0–0.2 × 0.1–0.3 mm; leaf blades without red blotch.
→ 62
62. Stems prostrate to decumbent; involucral gland appendages unequal (pair near sinus lunate to oblong, 0.1–0.2 × 0.1–0.3 mm, distal margins entire, crenulate, or irregularly sinuate, other pair rudimentary, 0–0.1 × 0.1–0.3 mm, distal margins crenulate or entire); peninsular Florida.
E. blodgettii
62. Stems prostrate; involucral gland appendages equal, forming narrow rim at edge of gland, 0.1–0.2 × 0.2–0.3 mm, distal margins entire or crenulate; widespread, including peninsular Florida.
E. serpens
59. Stipules usually distinct, occasionally connate basally (rarely connate to middle in E. platysperma), not forming conspicuous, deltate, ligulate, or ovate scale.
→ 63
63. Perennial herbs or subshrubs with thickened and often woody rootstocks.
→ 64
64. Seeds 1.6–2.4 mm.
→ 65
65. Capsules 2.8–3.3 × 2.8–3.4 mm; involucres broadly campanulate to hemispheric, 1.7–2.2 × 1.5–2.7 mm; styles 0.7–0.9 mm; leaf blades ovate or orbiculate-deltate to reniform-deltate, 5–17 × 4–16 mm.
E. perennans
65. Capsules 1.7–2.4 × 1.6–2.5 mm; involucres campanulate to turbinate or broadly cupulate, 0.8–1.7 × 0.8–1.8 mm; styles 0.3–0.4 mm; leaf blades lanceolate, linear- or oblong-lanceolate, ovate, or orbiculate, 3–11 × 0.8–7 mm.
→ 66
66. Stems usually erect, rarely slightly decumbent; leaf blades ovate to lanceolate or oblong- or linear-lanceolate, 3–11 × 0.8–3(–5) mm, apex acute to short acuminate, base short-tapered, occasionally one side rounded.
E. chaetocalyx
66. Stems usually prostrate, decumbent, or ascending, very rarely erect; leaf blades usually orbiculate to ovate, rarely almost lanceolate, 3–8 × 2.5–7 mm, apex rounded to obtuse, base slightly cordate to rounded or obtuse.
E. fendleri
64. Seeds 0.8–1.4 mm.
→ 67
67. Stipules usually glabrous (occasionally sparsely hairy with appressed uncinate hairs in E. deltoidea).
→ 68
68. Stems prostrate; stems and leaf blades glabrous or sparsely hairy with appressed uncinate hairs; s Florida.
E. deltoidea
68. Stems erect to ascending; stems and leaf blades usually villous, rarely glabrous; Texas.
E. villifera
67. Stipules pilose to hirsute.
→ 69
69. Capsules 1.6–1.7 × 1.6–1.9 mm; seeds 1.2–1.4 mm; involucral gland appendages absent; involucres 1–1.4 mm.
E. parishii
69. Capsules 1.1–1.4 × 1.1–1.4 mm; seeds 0.8–1.1 mm; involucral gland appendages present, occasionally forming rim at margin of gland; involucres 0.6–1.1 mm.
E. polycarpa
63. Annual, rarely short-lived perennial, herbs with taproots or spreading rootstocks.
→ 70
70. Capsules 4.7–5.5(–6) mm; seeds (2.8–)4.1–5.2 mm, bottle-shaped, strongly dorsiventrally compressed and weakly 3-angled in cross section, with linear carunclelike structure.
E. carunculata
70. Capsules 1–3.5(–4) mm; seeds 0.7–2.8 mm, not bottle-shaped, weakly dorsiventrally compressed or terete to sub-, 3-, or 4-angled in cross section, without carunclelike structure.
→ 71
71. Seeds terete or bluntly subangled in cross section (weakly dorsiventrally compressed in E. platysperma and E. polygonifolia, thus appearing semielliptic), usually smooth, occasionally rugose, minutely pitted, or obscurely wrinkled (E. platysperma with sharp, linelike, longitudinal ridges on adaxial side).
→ 72
72. Seeds (2–)2.2–2.8 mm, weakly dorsiventrally compressed in cross section.
→ 73
73. Involucral gland appendages present; leaf blade apices usually acute to mucronulate, rarely obtuse; capsules 2.7–3.2 × 2.2–2.9 mm; Arizona, California.
E. platysperma
73. Involucral gland appendages absent; leaf blade apices obtuse, often mucronulate; capsules 3–3.5(–4) × (2–)2.4–3 mm; Atlantic and Great Lakes shores.
E. polygonifolia
72. Seeds 0.7–2.1 mm, terete to bluntly sub- or 3-angled in cross section.
→ 74
74. Stems erect or ascending; leaf blades narrowly oblong to narrowly lanceolate-oblong; styles 0.5–1.4 mm; involucral gland appendages present, 0.4–2.5 mm; seeds bluntly 3-angled.
E. missurica
74. Stems prostrate to slightly ascending; leaf blades oblong, oblong-obovate, narrowly elliptic, or lanceolate, ovate, deltate or falcate; styles 0.2–0.6 mm; involucral gland appendages present or absent, (0–)0.1–1 mm; seeds terete to bluntly subangled.
→ 75
75. Leaf blades ovate to deltate or falcate; w United States.
E. ocellata
75. Leaf blades elliptic, oblong, or lanceolate; c United States to Gulf and Atlantic coasts.
→ 76
76. Leaf blades narrowly elliptic to lanceolate, 4–8 × 1–2 mm; seeds 1–1.3 mm; involucral gland appendages 0.1–0.2 mm, often rudimentary; s Florida.
E. cumulicola
76. Leaf blades oblong to oblong-elliptic or oblong-obovate, 4–15 × 2–6 mm; seeds 1.1–1.9 mm; involucral gland appendages absent or 0.1–1 mm; widespread, including s Florida.
→ 77
77. Leaf blades oblong or elliptic-oblong, 2–3 mm wide; involucral gland appendages (0–)0.1–0.5(–0.7) mm; styles 0.2–0.3 mm; coastal, Texas to Virginia.
E. bombensis
77. Leaf blades oblong, oblong-elliptic, or oblong-obovate, 2–6 mm wide; involucral gland appendages (0.1–)0.5–1 mm; styles 0.2–0.6 mm; not coastal, Texas north through c United States.
E. geyeri
71. Seeds usually 3–4-angled in cross section (± weakly angled in E. villifera), smooth to rugose or wrinkled, or with transverse ridges.
→ 78
78. Stems erect to ascending.
→ 79
79. Stems glabrous; stipules triangular; involucral gland appendages (0–)0.1–0.2 mm; seeds 0.7–1 mm; Florida.
E. porteriana
79. Stems usually villous, rarely glabrous; stipules filiform; involucral gland appendages 0.2–0.4 mm; seeds 1–1.4 mm; Texas.
E. villifera
78. Stems prostrate or reclining.
→ 80
80. Stipules filiform; leaf blade bases cordate to rounded; seeds 1.8–2.1 mm, smooth to rugose.
E. cordifolia
80. Stipules subulate or scalelike; leaf blade bases rounded, oblique, or cuneate; seeds 0.8–2 mm, sculpture various (if 1.5–2 mm then with 5–7 faint transverse ridges).
→ 81
81. Involucres 0.4–0.6 mm.
E. micromera
81. Involucres 0.6–1.8 mm (usually more than 0.8 mm).
→ 82
82. Seeds 1.3–2 mm.
→ 83
83. Involucral glands subcircular; involucral gland appendages present; seeds 1.3–1.5 mm; leaf blades oblong, ovate-oblong, or narrowly elliptic-oblong; vicinity of Rio Grande, w Texas.
E. golondrina
83. Involucral glands elliptic; involucral gland appendages absent; seeds 1.5–2 mm; leaf blades orbiculate, oval, or shortly oblong; widespread in Texas.
E. simulans
82. Seeds 0.8–1.2 mm.
→ 84
84. Seeds smooth or faintly rippled; involucral glands oblong, appendages 0.1–0.2 mm; leaf blade apices obtuse to acute.
E. polycarpa
84. Seeds with deep transverse ridges; involucral glands subcircular to slightly elliptic, appendages (0–)0.1–0.4 mm; leaf blade apices rounded, occasionally slightly emarginate.
E. theriaca
Source FNA vol. 12, p. 283. FNA vol. 12, p. 251. Authors: Victor W. Steinmann, Jeffery J. Morawetz, Paul E. Berry, Jess A. Peirson, Ya Yang.
Parent taxa Euphorbiaceae > Euphorbia > sect. Anisophyllum Euphorbiaceae > Euphorbia
Sibling taxa
E. aaron-rossii, E. abramsiana, E. acuta, E. agraria, E. albomarginata, E. alta, E. angusta, E. antisyphilitica, E. arizonica, E. astyla, E. austrotexana, E. bicolor, E. bifurcata, E. bilobata, E. blodgettii, E. bombensis, E. brachycera, E. capitellata, E. carunculata, E. chaetocalyx, E. chamaesula, E. cinerascens, E. commutata, E. conferta, E. cordifolia, E. corollata, E. crenulata, E. cumulicola, E. cuphosperma, E. curtisii, E. cyathophora, E. cyparissias, E. davidii, E. deltoidea, E. dendroides, E. dentata, E. discoidalis, E. eriantha, E. exigua, E. exserta, E. exstipulata, E. falcata, E. fendleri, E. florida, E. floridana, E. garberi, E. georgiana, E. geyeri, E. glyptosperma, E. golondrina, E. gracillima, E. graminea, E. helioscopia, E. helleri, E. heterophylla, E. hexagona, E. hirta, E. hooveri, E. humistrata, E. hypericifolia, E. hyssopifolia, E. indivisa, E. innocua, E. inundata, E. ipecacuanhae, E. jaegeri, E. jejuna, E. laredana, E. lasiocarpa, E. lata, E. lathyris, E. longicruris, E. lurida, E. macropus, E. maculata, E. marginata, E. meganaesos, E. melanadenia, E. mendezii, E. mercurialina, E. mesembrianthemifolia, E. micromera, E. misera, E. missurica, E. myrsinites, E. nephradenia, E. nutans, E. oblongata, E. ocellata, E. ophthalmica, E. ouachitana, E. parishii, E. parryi, E. pediculifera, E. peplidion, E. peplus, E. perennans, E. pergamena, E. pinetorum, E. platyphyllos, E. platysperma, E. polygonifolia, E. polyphylla, E. porteriana, E. prostrata, E. pubentissima, E. purpurea, E. radians, E. rayturneri, E. revoluta, E. roemeriana, E. rosescens, E. schizoloba, E. serpens, E. serpillifolia, E. serrata, E. serrula, E. setiloba, E. simulans, E. spathulata, E. stictospora, E. strictior, E. telephioides, E. terracina, E. tetrapora, E. texana, E. theriaca, E. thymifolia, E. tithymaloides, E. trachysperma, E. trichotoma, E. vallis-mortae, E. velleriflora, E. vermiculata, E. villifera, E. virgata, E. wrightii, E. yaquiana
Subordinate taxa
E. polycarpa var. polycarpa
E. abramsiana, E. acuta, E. albomarginata, E. angusta, E. arizonica, E. astyla, E. blodgettii, E. bombensis, E. capitellata, E. carunculata, E. chaetocalyx, E. cinerascens, E. conferta, E. cordifolia, E. cumulicola, E. deltoidea, E. fendleri, E. florida, E. garberi, E. geyeri, E. glyptosperma, E. golondrina, E. gracillima, E. hirta, E. hooveri, E. humistrata, E. hypericifolia, E. hyssopifolia, E. indivisa, E. jaegeri, E. jejuna, E. laredana, E. lasiocarpa, E. lata, E. maculata, E. meganaesos, E. melanadenia, E. mendezii, E. mesembrianthemifolia, E. micromera, E. missurica, E. nutans, E. ocellata, E. ophthalmica, E. parishii, E. parryi, E. pediculifera, E. perennans, E. pergamena, E. platysperma, E. polycarpa, E. polygonifolia, E. porteriana, E. prostrata, E. rayturneri, E. revoluta, E. serpens, E. serpillifolia, E. serrula, E. setiloba, E. simulans, E. stictospora, E. theriaca, E. thymifolia, E. trachysperma, E. vallis-mortae, E. velleriflora, E. vermiculata, E. villifera
Synonyms Chamaesyce polycarpa Anisophyllum, Chamaesyce
Name authority Bentham: Bot. Voy. Sulphur, 50. (1844) Roeper: in J. É. Duby, Bot. Gall. 1: 412. (1828)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers