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

Croton heptalon

Croton ciliatoglandulifer

woolly croton

bush croton, Mexican croton
Habit Herbs, annual, 5–15 dm, monoecious; stems, leaves, and buds whitish-hairy when young, becoming glabrate. Shrubs, 2–10 dm, monoecious.
Stems

well branched distally, stellate-hairy.

± dichotomously branched, stellate-hairy.
Leaves

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.

not clustered;

stipules glandular-ciliate, 2–3 mm;

petiole 1–3.5 cm, 1/2–7/10+ leaf blade length, stipitate-glandular at apex;

blade ovate, 2–5 × 1–3 cm, base rounded to subcordate, margins entire glandular-ciliate, apex acute to acuminate, abaxial surface pale green, densely stellate-hairy, adaxial surface darker green, sparsely stellate-hairy.
Inflorescences

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

bisexual, racemes, 1–2.5 cm, staminate flowers 3–10, pistillate flowers 1–8.
Pedicels

staminate 2–4 mm, pistillate 1–2 mm.

staminate 0.5–1.5 mm, pistillate 2–3 mm.
Staminate flowers

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.

sepals 5, 3.5–4 mm, abaxial surface stellate-hairy;

petals 5, spatulate, 2.5–3 mm, abaxial surface glabrous;

stamens 20–30.
Pistillate flowers

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.

sepals 5, equal, 3–5 mm, margins entire, glandular-ciliate, apex straight, abaxial surface stellate-hairy;

petals 0;

ovary 3-locular;

styles 3, 4–5 mm, 4-fid, terminal segments 12.
Capsules

6–8 × 6–7 mm, smooth;

columella tipped with 3-pronged grappling hooklike appendage.

4–5 × 5–7 mm, smooth;

columella apex with 3 rounded, inflated lobes.
Seeds

4–5 × 2–2.5 mm, shiny.

4–5.5 × 2.5–3 mm, shiny.
2n

= 20.

Croton heptalon

Croton ciliatoglandulifer
Phenology Flowering May–Dec. Flowering Oct–Dec.
Habitat Beaches, coastal dunes, roadsides. Rocky forested slopes, sandy flats.
Elevation 0–50 m. (0–200 ft.) 0–2200 m. (0–7200 ft.)
Distribution
from FNA
TX; e Mexico
[BONAP county map]
from FNA
AZ; TX; Mexico; West Indies
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Croton ciliatoglandulifer is characterized by the glandular projections on the leaf blade margins, stipules, and pistillate sepals. The species is closely related to C. humilis and C. soliman, which may intergrade with it. Croton ciliatoglandulifer presents an interesting disjunction in the United States from lowland southern Texas (0–150 m elevation) to upland southern Arizona (to 2200 m elevation).

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 12, p. 217. FNA vol. 12, p. 213.
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. 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
C. alabamensis, C. argenteus, C. argyranthemus, C. californicus, C. capitatus, C. cortesianus, C. coryi, C. dioicus, C. elliottii, C. fruticulosus, C. glandulosus, 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
Synonyms Oxydectes heptalon, C. albinoides, C. capitatus var. albinoides, C. engelmannii var. albinoides, C. muelleri var. albinoides, Heptallon aromaticum
Name authority (Kuntze) B. W. van Ee & P. E. Berry: Syst. Bot. 35: 159. (2010) Ortega: Nov. Pl. Descr. Dec., 51. (1797) — (as cilato-glanduliferum)
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 Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

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