PLANT: Shrubs, armed. STEMS: several to many, erect to ascending, green, rigid; branches mostly opposite, jointed, thorn-tipped, villous when young, glabrescent with age; bud-scales absent. LEAVES: early deciduous, opposite, subopposite, or fascicled, short-petiolate; blades lanceolate to ovate, pinnately veined, entire, sparsely to densely villous. INFLORESCENCE: axillary, cymose, of several flowers. FLOWERS: perfect, pedicellate; hypanthium hemispheric, 2-3 mm in diameter, slightly villous; sepals 5, triangular, whitish and petaloid; petals 5; stamens 5; ovary superior; stigma obscurely 3-parted. FRUITS: dry, loculicidal capsules, 3-loculed, tan, spheric, 5 mm long, 5 mm wide, beaked by a persistent style, glabrous; seeds 3, 1 per locule, plano-convex. NOTES: NOTES 2 spp. in the Southwestern U.S. and Mex. (1 in AZ). (named for Adolphe Brongniart, Rhamnaceae taxonomist, 1801-1876). An essentially leafless plant with photosynthetic stems. Both species are seemingly rare. REFERENCES: Kyle Christie, Michael Currie, Laura Smith Davis, Mar-Elise Hill, Suzanne Neal, and Tina Ayers, 2006 Vascular Plants of Arizona: Rhamnaceae. CANOTIA 2(1): 23-46.
