Croton sonorae

Torrey

in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 194. 1859.

Common names: Sonora croton
Synonyms: Croton attenuatus M. E. Jones C. pringlei S. Watson
Treatment appears in FNA Volume 12. Treatment on page 223. Mentioned on page 209.

Shrubs, 8–16 dm, monoecious. Stems much-branched distally, canescent when young, becoming glabrate. Leaves sometimes clustered near inflorescences; stipules subulate, to 1 mm; petiole 0.4–1 cm, 1/4–1/2 leaf blade length, glands absent at apex; blade ovate to broadly lanceolate, 0.8–4 × 0.6–2 cm, base cuneate to rounded or cordate, margins entire, not undulate, ciliate-glandular, apex acute to acuminate, abaxial surface pale green, sparsely whitish stellate-hairy, adaxial surface darker green, glabrate. Inflorescences bisexual or staminate, racemes, 2–14 cm, staminate flowers 10–25, pistillate flowers 3–5(–8). Pedicels: staminate 1–1.5 mm, pistillate 1–4 mm. Staminate flowers: sepals 5, 1–1.5 mm, abaxial surface sparsely stellate-hairy; petals 5, lanceolate, 1.5–2 mm, abaxial surface glabrous except margins villous; stamens 13–16. Pistillate flowers: sepals 5, equal, 1.5–2 mm, margins entire, apex incurved, abaxial surface sparsely stellate-hairy; petals papillae, 0.5 mm; ovary 3-locular; styles 3, 2–3 mm, 2-fid, terminal segments 6. Capsules 7–8 × 5–6 mm, smooth; columella apex with 3 rounded, inflated lobes. Seeds 6–7 × 3–4 mm, shiny.


Phenology: Flowering Jul–Sep.
Habitat: Rocky slopes, desert scrub.
Elevation: 500–1100 m.

Distribution

V12 746-distribution-map.jpg

Ariz., Mexico (Baja California, Sonora).

Discussion

Croton sonorae is widely distributed in Mexico and extends into southern Arizona in Maricopa, Pima, and Pinal counties.

Selected References

None.

Lower Taxa

None.