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

Arizona sandmat, Arizona spurge

Everglade key sandmat

Habit Herbs, annual or short-lived perennial, with slender to slightly thickened taproot. Herbs, annual, with taproot.
Stems

erect to ascending, 10–30 cm, uniformly pilose with glistening hairs.

prostrate, ascending, to erect, 10–45 cm, pilose.

Leaves

opposite;

stipules distinct, deltate, (0–)0.1 mm, glabrous or with few scattered hairs;

petiole 0.4–1.5 mm, pilose with glistening hairs;

blade usually ovate, rarely elliptic, 3–11 × 2–7 mm, base asymmetric, one side cuneate to rounded, other side rounded to strongly cordate, margins entire, apex obtuse or acute, surfaces pilose with glistening hairs; 3-veined from base but usually only midvein conspicuous.

opposite;

stipules distinct, subulate, 1–2 mm, pilose;

petiole 0.9–1.5 mm, pilose;

blade oblanceolate to elliptic, 3–10 × 1–4 mm, base asymmetric, obtuse to hemicordate, margins coarsely serrate, sometimes revolute, apex rounded to acute, abaxial surface sparsely hispidulous to strigillose (densely so on young leaves), adaxial surface glabrous; 3-veined from base but only midvein conspicuous.

Involucre

urceolate, 1.1–1.3 × 0.5–0.9 mm, glabrous or pilose with glistening hairs;

glands 4, dark maroon, usually oblong to reniform, rarely almost circular, 0.2 × 0.2–0.4 mm;

appendages white to pink, oblong, flabellate, oblong, or elliptic, 0.3–0.6 × 0.6–0.9 mm, distal margin entire or crenulate.

campanulate, 1.1–1.4 × 0.5–0.7 mm, pilose;

glands 4, red, narrowly reniform, 0.1 × 0.2–0.4 mm;

appendages pink to red, larger 2 petal-like, smaller 2 elliptic, 0.4–1 × 0.3–0.5 mm, distal margin erose.

Staminate flowers

5–12.

5–8.

Pistillate flowers

ovary pilose, styles 0.5–0.6 mm, 2-fid 1/2 length.

ovary pilose;

styles 0.4–0.8 mm, 2-fid at apex.

Capsules

broadly ovoid to subglobose, 1.4–1.8 mm diam., pilose;

columella 1.1–1.4 mm.

conic or truncate-ovoid, 1–1.2 mm diam., pilose;

columella 0.9–1.1 mm.

Seeds

gray to light brown, ovoid, 4-angled in cross section, 0.9–1.1 × 0.5–0.6 mm, rugose with 2–5 irregular transverse ridges that sometimes pass through abaxial keel.

orange-brown, glaucous, oblong, 4-angled in cross section, 0.7–0.8 × 0.4–0.5 mm, slightly rugose and with 3–4 transverse ridges.

Cyathia

solitary at distal nodes;

peduncle 0.7–3.6 mm.

solitary at distal nodes (appearing clustered at points of new growth);

peduncle 0.4–0.6 mm.

Euphorbia arizonica

Euphorbia conferta

Phenology Flowering and fruiting year-round in response to sufficient moisture. Flowering and fruiting year-round.
Habitat Washes and rocky slopes, sometimes on limestone, desert scrub communities often with creosote-bush, riparian forests, mesquite woodlands, oak chaparral. Sandy, disturbed, wet areas, often roadsides.
Elevation 100–1400 m. (300–4600 ft.) 0–10 m. (0–0 ft.)
Distribution
from FNA
AZ; CA; NM; TX; Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, Sonora)
[WildflowerSearch map]
[BONAP county map]
from FNA
FL
[BONAP county map]
Discussion

Euphorbia arizonica is distinctive and easily recognized by its glistening, translucent hairs that appear somewhat glutinous and are most apparent on the stems.

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

Euphorbia conferta is known only from Broward, Miami-Dade, and Monroe counties in southern Florida.

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

Source FNA vol. 12, p. 260. FNA vol. 12, p. 264.
Parent taxa Euphorbiaceae > Euphorbia > sect. Anisophyllum Euphorbiaceae > Euphorbia > sect. Anisophyllum
Sibling taxa
E. aaron-rossii, E. abramsiana, E. acuta, E. agraria, E. albomarginata, E. alta, E. angusta, E. antisyphilitica, 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. 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. 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
Synonyms Chamaesyce arizonica Chamaesyce conferta
Name authority Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 186. (1859) (Small) B. E. Smith: J. Elisha Mitchell Sci. Soc. 62: 82. (1946)
Web links