Croton pottsii

(Klotzsch) Müller Arg.

in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 15(2): 561. 1866.

Common names: Leatherweed
Basionym: Lasiogyne pottsii Klotzsch in B. Seemann, Bot. Voy. Herald, 278. 1853
Treatment appears in FNA Volume 12. Treatment on page 221. Mentioned on page 209.

Herbs, perennial, 1–6 dm, monoecious or dioecious. Stems several from base, sparsely branched distally, stellate-hairy. Leaves sometimes clustered near inflorescences; stipules rudimentary; petiole 0.5–2 cm, glands absent at apex; blade ovate-oblong, proximal rounder, distal more ovate-elliptic, 1–6 × 1–3 cm, base rounded, margins entire, apex rounded to acute, both surfaces pale to ashy green, softly stellate-hairy. Inflorescences bisexual or unisexual, racemes, 0.5–2.5 cm, staminate and pistillate flowers each (12–)20–25. Pedicels: staminate 1.5–6 mm, pistillate 1–3.5 mm, ± recurved in fruit. Staminate flowers: sepals (4–)5, 1–1.5 mm, abaxial surface densely stellate-hairy; petals (4–)5, oblong-lanceolate, 1–1.3 mm, abaxial surface glabrous except margins villous; stamens 10–15. Pistillate flowers: sepals 5, equal, 1.5–3 mm, margins entire, apex straight to slightly incurved, abaxial surface glabrous except stellate-hairy at apex; petals 0; ovary 3-locular; styles 3, 0.5–4.5 mm, 2-fid to base, terminal segments 6. Capsules 4–6(–7) × 4–5 mm, smooth; columella apex with 3 sharp projections. Seeds 3.5–4 × 2–2.5 mm, shiny. 2n = 20.

Distribution

V12 898-distribution-map.jpg

Ariz., N.Mex., Tex., n, c Mexico.

Discussion

Varieties 2 (2 in the flora).

The affinities of Croton pottsii lie with C. lindheimerianus and C. monanthogynus.

Selected References

None.

Key

1 Stems straight; erect radii of stellate hairs shorter than lateral radii, thus pubescence appearing appressed and smooth; leaf blades 1.6–6 cm; racemes mostly 1.1–2.5 cm; styles 1.1–4.5 mm; capsules 4–6(–7) mm. Croton pottsii var. pottsii
1 Stems somewhat zigzag; erect radii of stellate hairs longer than lateral radii, thus pubescence appearing ± shaggy; leaf blades usually 1–1.4 cm; racemes mostly 0.5–0.9 cm; styles usually 0.5–1 mm; capsules 4 mm. Croton pottsii var. thermophilus