California box-thorn

Lycium californicum var. arizonicum A. Gray; L. californicum var. interior F. Chiang; L. carinatum S. Watson

Shrubs prostrate to erect, 0.1–2 m; bark yellowish to gray; stems glabrous. Leaves: blade spheric to spatulate, 2–25 × 1–3 mm, fleshy to succulent, surfaces glabrous. Inflorescences 2–3-flowered fascicles or soli­tary flowers. Pedicels 1–5 mm. Flowers bisexual or pis­tillate, 4-merous; calyx campanulate, 2–4-lobed, 2–3 mm, lobe lengths 0.3 times tube; corolla white to pale purple, campanulate, 2–6 mm, lobe lengths to 1 times tube; stamens exserted (bisexual flowers) or included, with nonfunctional anthers (pistillate flow­ers). Berries orange to red, ovoid, 2–6 mm, thinly fleshy. Seeds 2, each enclosed by a hard layer. 2n = 24, 36, 48.

Flowering Jan–Mar(–Sep). Saline flats, coastal flats and bluffs (Mediterranean floristic province, Sonoran Desert, and restricted locations in the Chihuahuan Desert); 0–500 m; Ariz., Calif.; Mexico (Baja California, Baja California Sur, Coahuila, San Luis Potosí, Sinaloa, Sonora, Zacatecas).

Within the flora area, Lycium californicum occurs in southern Arizona and southwestern California. Popula­tions of L. californicum vary in both ploidy (diploid to tetraploid) and sexual system (hermaphroditic to gender dimorphic). Gender dimorphic populations are mor­phologically gynodioecious (functionally dioecious), and plants are sexually dimorphic for flower size, with smaller pistillate flowers.

SELECTED REFERENCE Miller, Jill S. et al. 2016. Correlated poly­morphism in cytotype and sexual system within a monophyletic species, Lycium californicum. Ann. Bot. (Oxford) 117: 307–317.