矮大戟 ai da ji

Euphorbia korovinii Pavlov.

Shrublets, very densely branched, 5-7(-15) cm tall. Rootstock a woody taproot, single, 10-20 cm × 5-10 mm thick, many branched at apex. Stems densely clustered, many branched from base, 1-1.5 mm thick, upper parts mostly unbranched, glabrous or minutely puberulent. Leaves alternate; stipules absent; basal scale-leaves overlapping, sometimes persistent; petiole absent; leaf blade obovate to elliptic, somewhat thickened, 6-8 × 3-5 mm, both surfaces glabrous, base cuneate, margin entire, apex acute; midrib inconspicuous, lateral veins invisible. Inflorescence a terminal pseudumbel; primary involucral leaves and rays (2-)4, similar to normal leaves; rays 0.6-1.5 cm, secondary branching rare; cyathophylls 2, similar to normal leaves but smaller and broader. Cyathium subsessile; involucre cuplike, 2-2.5 × 2-2.5 mm, lobes obtusely triangular; glands 4, pale yellow-brown, ± fan-shaped, spreading. Male flowers many, only slightly exserted from involucre. Female flower: ovary pedicel up to 4-6 mm and exserted from cup; ovary smooth, glabrous; styles almost free, persistent, easily lost; style arms shortly 2-lobed, not enlarged. Fruiting pedicel reflexed after dehiscence; capsule ovoid-globose, 3.5-4 × ca. 3 mm, smooth, glabrous. Seeds compressed tetragonal, 2-2.5 × ca. 1.5 mm, with clear spots; caruncle peltate, sessile. Fl. and fr. May-Jul.

Rock slopes, scrub, steppes. N Xinjiang [Kazakhstan, Kyrgyzstan, Russia (W Siberia), Tajikistan, Turkmenistan, Uzbekistan; SW Asia (Iran)].

Euphorbia humilis is easily identified within the Flora area by its small stature, as well as by its succulent leaf blades.