Wiggins’ croton Wiggins’ croton

Croton arenicola Rose & Standley, Contr. U.S. Natl. Herb. 16: 12. 1912, not Small 1905

Shrubs, 2–10 dm, dioecious. Stems densely branched, appressed-lepidote. Leaves not clustered; stipules absent; petiole 1–4 cm, usually less than 1/2 blade length, glands absent at apex; blade narrowly elliptic to linear-oblong, 2–8.5 × 0.6–1.5 cm, more than 2 times as long as wide, base obtuse, margins entire, apex obtuse to rounded, abaxial surface pale green, adaxial surface darker green, both densely pale stellate-lepidote. Inflorescences unisexual, racemes or thyrses; staminate 1–3.5(–10) cm, flowers 3–8(–15); pistillate 0.5–1 cm, flowers 1–6. Pedicels: staminate 1–7 mm, pistillate 1–2 mm (4–7 mm in fruit). Staminate flowers: sepals 5, 1 mm, abaxial surface stellate-hairy; petals 0; stamens 10–15. Pistillate flowers: sepals 5, equal, 2 mm, margins entire, apex incurved, abaxial surface stellate-lepidote; petals 0; ovary 3-locular; styles 3, 1.5–2.5 mm, 2–3 times 2-fid, terminal segments 12–24. Capsules 7–10 × 6–8 mm, smooth; columella 3-winged. Seeds 6.5–7 × 2–3 mm, dull. 2n = 28.

Flowering Feb–May. Sand dunes; 10–100 m; of conservation concern; Ariz., Calif.; Mexico (Baja California, Sonora).

Croton wigginsii is closely related to C. californicus but more robust in its habit and floral features, and is restricted to sand dunes in a limited area of the Sonoran Desert. In the flora area, C. wigginsii is known only from Yuma County, Arizona, and Imperial County, California.