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

black-seed spurge

roadside sandmat

Habit Herbs, annual, with slender taproot. Herbs, annual or perennial, often robust, with slender to moderately thickened taproot.
Stems

erect, branched, 10–35 cm, glabrous or strigillose (especially when young and around nodes).

erect to ascending, 30–100 cm, pilose to tomentose.

Leaves

opposite proximally, alternate distally;

stipules 0.1–0.2 mm;

petiole 1–4(–6) mm, glabrous, sericeous or strigillose;

blade linear to narrowly elliptic, 8–52 × 2–7 mm, base attenuate, margins entire, ciliate-strigose, apex acute, abaxial surface sparsely strigillose to sericeous, adaxial surface usually glabrous;

venation obscure, only midvein conspicuous.

opposite;

stipules distinct when young, connate into deltate scale when older, erose to laciniate, with dark glands at margin or base, 0.5–1.3 mm, pilose;

petiole 0.5–2 mm, glabrescent or pilose;

blade ovate or oblong, sometimes slightly falcate, 8–46 × 3–21 mm, base asymmetric, obtuse to hemicordate, margins serrulate, apex obtuse or acute, surfaces often with red spot in center, pilose to sericeous; palmately 3–5(–7)-veined from base.

Involucre

obconic, 0.9–1.5 × 0.9–1.3 mm, strigillose to pilose;

glands 5, yellow or pink, U-shaped, 0.2–0.3 × 0.4–0.5 mm;

appendages greenish, white, or pink, forming narrow rim around gland, or ovate, oblong, or obovate and usually 2-fid, rarely rudimentary, 0.2–1.4 × 0.2–0.6 mm, entire.

obconic, 0.9–1.3 × 0.8–1.2 mm, pilose to sericeous;

glands 4, yellow or pink, circular or oblong, 0.1–0.3 mm diam.;

appendages white or pink, oblong, flabellate, or suborbiculate, 0.1–0.6 × 0.2–1 mm, entire or crenate.

Staminate flowers

20–25.

15–25.

Pistillate flowers

ovary glabrous, puberulent, strigillose, or pilose;

styles 0.5–0.8 mm, 2-fid 1/3–1/2 length.

ovary densely pilose to sericeous with yellowish hairs;

styles 0.6–0.9 mm, 2-fid 1/2 length, filiform.

Capsules

oblate, 1.5–2.6 × 2.1–3.3 mm, glabrous or puberulent, strigillose, or pilose;

columella 1.2–2.1 mm.

subglobose to broadly ovoid, 1.7–2 mm diam., pilose to sericeous with yellowish hairs;

columella 1.5–1.7 mm.

Seeds

brown to grayish black, narrowly ovoid, 3- or 4-angled in cross section, sometimes obscurely so, 1.3–1.9 × 1–1.4 mm, tuberculate, often with shallow depressions;

caruncle absent.

dark reddish brown to almost black, plumply ovoid, 4-angled in cross section, 1.2–1.3 × 0.7–0.8 mm, with 2 inconspicuous rows of 3–5 shallow depressions separated by low ridges.

Cyathia

solitary at distal nodes or in weakly defined cymes or dichasia, dichasial bracts and distal stem leaves wholly green;

peduncle 0.5–3.6 mm, strigillose.

in dense, usually terminal, capitate glomerules, with reduced, bractlike leaves subtending cyathia;

peduncle 0.8–2.3 mm.

2n

= 32.

Euphorbia bilobata

Euphorbia lasiocarpa

Phenology Flowering and fruiting spring–fall. Flowering and fruiting year-round.
Habitat Sandy and rocky soils on slopes and canyon bottoms in pine-juniper woodlands, oak woodlands, grasslands. Open disturbed areas, mostly along roadsides and railroad tracks.
Elevation 1400–2600 m. (4600–8500 ft.) 0–10 m. (0–0 ft.)
Distribution
from FNA
AZ; NM; TX; Mexico (Chihuahua, Durango, Sonora)
[WildflowerSearch map]
[BONAP county map]
from FNA
FL; Mexico; Central America; South America; West Indies [Introduced in North America]
[BONAP county map]
Discussion

In Texas, Euphorbia bilobata is known only from Jeff Davis County.

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

Euphorbia lasiocarpa is similar to E. hypericifolia but is much more hairy on its stems and leaves. Euphorbia lasiocarpa is widespread throughout tropical America, but its precise native range in the New World is not clear. In the flora area, E. lasiocarpa is found in southern Florida, where it is likely introduced.

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

Source FNA vol. 12, p. 243. FNA vol. 12, p. 275.
Parent taxa Euphorbiaceae > Euphorbia > sect. Alectoroctonum Euphorbiaceae > Euphorbia > sect. Anisophyllum
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. 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. polycarpa, 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
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. 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. polycarpa, 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
Synonyms Chamaesyce lasiocarpa
Name authority Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 190. (1859) Klotzsch: Nov. Actorum Acad. Caes. Leop.-Carol. Nat. Cur. 19(suppl. 1): 414. (1843)
Web links