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sand croton, sand or tooth-leaf or Tropic croton, tooth-leaf croton, Tropic croton, vente conmigo

woolly croton

Habit Herbs, annual, 1–12 dm, monoecious. Herbs, annual, 5–15 dm, monoecious; stems, leaves, and buds whitish-hairy when young, becoming glabrate.
Stems

much branched distally, usually coarsely stellate-hairy, rarely glabrescent.

well branched distally, stellate-hairy.

Leaves

not clustered;

stipules linear-subulate, glandular or not, to 0.5 mm or absent;

petiole 0.2–1 cm, glands at apex 2, yellow, sessile to shortly stipitate, cuplike;

blade ovate proximally, oblong-lanceolate distally, 0.6–3.5(–7) × 0.3–1.5(–3) cm, base obtuse to truncate, margins coarsely crenate to serrate-dentate, apex obtuse to rounded, both surfaces green, stellate-hairy, glabrate, or rarely glabrous.

not clustered;

stipules linear, 2–7 mm;

petiole 0.5–5 cm, glands absent at apex;

blade ovate-lanceolate, 3–10 × 1–5 cm, base cordate to rounded, margins entire, apex acute, abaxial surface pale green, not appearing brown-dotted, no stellate hairs with brown centers, adaxial surface darker green, both stellate-hairy.

Inflorescences

bisexual, racemes, 1–3 cm, staminate flowers 10–20, pistillate flowers 1–4.

bisexual, racemes, 2–4 cm, staminate flowers 3–10, pistillate flowers 4–8.

Pedicels

staminate 0.8–2 mm, pistillate 0–5 mm.

staminate 2–4 mm, pistillate 1–2 mm.

Staminate flowers

sepals 5, 0.8–1.2 mm, abaxial surface stellate-hairy;

petals 5, oblanceolate, 1–1.3 mm, abaxial surface glabrous except margins ciliate;

stamens 7–13.

sepals (4–)5, 1–2 mm, abaxial surface stellate-hairy;

petals 5, linear-oblong-lanceolate, 1–1.5 mm, abaxial surface stellate-hairy;

stamens 9–12.

Pistillate flowers

sepals 5, subequal, 6–7.5 mm, margins entire, apex straight to slightly incurved, abaxial surface glabrous except stellate-hairy apically;

petals 0 or 5, rudimentary;

ovary 3-locular;

styles 3, 1–2.5 mm, deeply 2-fid, terminal segments 6.

sepals 7–8, subequal, 3–6 mm, margins entire, apex straight to slightly incurved, abaxial surface whitish appressed-tomentose;

petals 0;

ovary 3-locular;

styles 3, 3–4 mm, 4-fid, terminal segments 12.

Capsules

3.5–6 × 4–5 mm, smooth;

columella 3-angled.

6–8 × 6–7 mm, smooth;

columella tipped with 3-pronged grappling hooklike appendage.

Seeds

3–4 × 2–2.5 mm, shiny.

4–5 × 2–2.5 mm, shiny.

2n

= 16.

Croton glandulosus

Croton heptalon

Phenology Flowering May–Dec.
Habitat Beaches, coastal dunes, roadsides.
Elevation 0–50 m. (0–200 ft.)
Distribution
from FNA
AL; AR; DE; FL; GA; IA; IL; IN; KS; KY; LA; MD; MI; MN; MO; MS; NC; NE; NJ; NM; OH; OK; PA; SC; TN; TX; VA; WI; WV; Mexico; Central America; South America; West Indies
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; e Mexico
[BONAP county map]
Discussion

Varieties ca. 20 (5 in the flora).

Croton glandulosus is widespread in the New World, with a complex pattern of variation. The classification here follows B. W. van Ee et al. (2009).

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

Morphological differences among Croton heptalon and its multifid-styled relatives in sect. Heptallon, especially C. capitatus and C. lindheimeri, can be quite subtle. In general, C. heptalon can be distinguished from C. capitatus by its more elongate pistillate part of the inflorescence, non-recurving sepal tips in the pistillate flowers, and more cordate leaf bases on larger basal leaves. Whitish pubescence on its young growth and styles that branch once into four terminal segments distinguish C. heptalon from C. lindheimeri.

Croton muelleri J. M. Coulter, which is an illegitimate name, pertains here.

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

Key
1. Leaf blades glabrate or sparsely to moderately stellate-hairy.
→ 2
2. Plants 2–12 dm; leaf blades 2–7 cm.
var. septentrionalis
2. Plants 1–2 dm; leaf blades 0.6–2(–3) cm.
→ 3
3. Leaf blades glabrate, bases markedly 3-veined; petiole apical glands sessile; Florida.
var. floridanus
3. Leaf blades sparsely stellate-hairy, bases obscurely 3-veined; petiole apical glands stipitate; Kansas, New Mexico, Oklahoma, Texas.
var. lindheimeri
1. Leaf blades moderately to densely stellate-hairy.
→ 4
4. Leaf blades firm-thick, length mostly 2 times width or less, marginal teeth rounded; petiole apical glands sessile.
var. arenicola
4. Leaf blades membranous, length mostly more than 2 times width, marginal teeth pointed; petiole apical glands sessile or stipitate.
→ 5
5. Leaf blades 1–2(–3) × 0.3–0.8(–1.3) cm; petiole apical glands stipitate, circular when dry, 0.1–0.4 mm diam.
var. lindheimeri
5. Leaf blades 2–7 × 0.7–3 cm; petiole apical glands sessile, wavy-wrinkled when dry, 0.5–0.8 mm diam.
→ 6
6. Stems densely stellate-hairy, hairs spreading, radii unequal; leaf blades densely stellate-villous.
var. pubentissimus
6. Stems moderately stellate-hairy, hairs appressed, radii equal; leaf blades moderately stellate-hairy.
var. septentrionalis
Source FNA vol. 12, p. 215. FNA vol. 12, p. 217.
Parent taxa Euphorbiaceae > Croton Euphorbiaceae > Croton
Sibling taxa
C. alabamensis, C. argenteus, C. argyranthemus, C. californicus, C. capitatus, C. ciliatoglandulifer, C. cortesianus, C. coryi, C. dioicus, C. elliottii, C. fruticulosus, C. heptalon, C. humilis, C. incanus, C. leucophyllus, C. lindheimeri, C. lindheimerianus, C. linearis, C. michauxii, C. monanthogynus, C. parksii, C. pottsii, C. punctatus, C. sancti-lazari, C. setigerus, C. soliman, C. sonorae, C. suaveolens, C. texensis, C. wigginsii
C. alabamensis, C. argenteus, C. argyranthemus, C. californicus, C. capitatus, C. ciliatoglandulifer, C. cortesianus, C. coryi, C. dioicus, C. elliottii, C. fruticulosus, C. glandulosus, C. humilis, C. incanus, C. leucophyllus, C. lindheimeri, C. lindheimerianus, C. linearis, C. michauxii, C. monanthogynus, C. parksii, C. pottsii, C. punctatus, C. sancti-lazari, C. setigerus, C. soliman, C. sonorae, C. suaveolens, C. texensis, C. wigginsii
Subordinate taxa
C. glandulosus var. arenicola, C. glandulosus var. floridanus, C. glandulosus var. lindheimeri, C. glandulosus var. pubentissimus, C. glandulosus var. septentrionalis
Synonyms Decarinium glandulosum, Geiseleria glandulosa, Oxydectes glandulosa Oxydectes heptalon, C. albinoides, C. capitatus var. albinoides, C. engelmannii var. albinoides, C. muelleri var. albinoides, Heptallon aromaticum
Name authority Linnaeus: Syst. Nat. ed. 10, 2: 1275. (1759) — (as glandulosum) (Kuntze) B. W. van Ee & P. E. Berry: Syst. Bot. 35: 159. (2010)
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