Trees or shrubs, small to medium-sized, evergreen or deciduous. Leaves alternate, 3-veined from base, margin subentire to serrate; stipules usually changed into 1 or 2 lignified, erect or revurved spines. Flowers bisexual, 5-merous, perigynous, few to many in axillary, pedunculate cymes. Pedicel short, often elongated in fruit. Calyx tube hemispheric to dish-shaped; sepals free, deltoid, 1.5-2.5 × 1.5-2.5 mm, abaxially ± pubescent to glabrous, adaxially keeled, apex acute to weakly acuminate. Petals spatulate or unguiculate,1-2 mm, often enfolding stamens. Stamens free, 1.5-2 mm; filaments subulate, thin; anthers ovoid, latrorse. Disk adnate with calyx tube, pentagonal or rounded, thick, fleshy, glabrous. Ovary semi-inferior, 2- or 3-loculed, with 1 ovule per locule, slightly immersed in disk; style cylindric or flattened, with 2 or 3 ± diverging stylar branches. Fruit a dry, indehiscent, disk- to cup-shaped or hemispheric, winged drupe, base ± distinctly conical, often with remains of calyx tube, apex rounded to ± flattened; mesocarp leathery to corky; endocarp lignified. Seeds brownish, shiny, obovoid to ovoid; endosperm scanty, cotyledons flat.
Shrubs [or trees], sometimes clambering, armed with stipular spines; bud scales present. Leaves deciduous [persistent], alternate; blade not gland-dotted; 3-veined from base (acrodromous), secondary veins distal to basal veins well developed. Inflorescences axillary, cymes; peduncles and pedicels not fleshy in fruit. Pedicels present. Flowers bisexual; hypanthium hemispheric to patelliform, 2–3 mm wide; sepals 5, spreading, pale yellow, deltate, keeled adaxially; petals 5, white, hooded, obovate, clawed; nectary fleshy, filling hypanthium, margin entire or 5-angled; stamens 5; ovary 1/2-inferior, 2–3-locular; styles 2–3, connate proximally. Fruits samaras. x = 12.
SELECTED REFERENCES Burge, D. O. and S. R. Manchester. 2008. Fruit morphology, fossil history, and biogeography of Paliurus (Rhamnaceae). Int. J. Pl. Sci. 169: 1066–1085. Schirarend, C. and M. N. Olabi. 1994. Revision of the genus Paliurus Tourn. ex Mill. (Rhamnaceae). Bot. Jahrb. Syst. 116: 333–359.
|Christ-thorn [Classical Greek name, perhaps derived from pálin, again or once more, and oúron or oureó, urine or to make water, alluding to diuretic properties of roots and leaves of P. spina-christi]|