Description from Flora of China
Platytaenia rubtzovii Schischkin in Schischkin & Bobrov, Fl. URSS 17: 357. 1951; Zosima rubtzovii (Schischkin) M. Hiroe.
Plants 40–60 cm tall. Taproot 1–2 cm across. Stem profusely branched, villose. Basal leaves 2-pinnate; ultimate segments linear, 4–6 × ca. 1 mm, puberulent. Cauline leaves similar to the basal, reduced upward. Umbels terminal and many lateral, 3–8 cm across; bracts 2–3, lanceolate, villose, membranous at margins; rays 7–13, unequal, 1.5–3 cm, pubescent; bracteoles 5, similar to the bracts; umbellules 15–20-flowered. Calyx teeth conspicuous, triangular. Petals white or yellowish-white, medial veins purple. Fruit ovoid, 5–7 × 3–4 mm, glabrous; dorsal and intermediate ribs filiform, lateral ribs broadly winged; vittae extending to base of mericarp, commissure vittae shorter than dorsal. Seed face plane. Fl. and fr. Jun–Aug.
Pebbly slopes, rock crevices. N Xinjiang (Ili) [Kazakhstan].