Stems erect or ascending, not rooting nodally, villous, not bulbous-based. Tuberous roots absent. Basal leaf blades broadly spatulate in outline, 1-2×-dissected, 0.9-3.8 × 0.5-1.5 cm, segments linear, margins entire, apex obtuse to acuminate. Flowers: receptacle glabrous; sepals spreading, 3-6 × 1-2 mm, villous; petals yellow, 3-5 × 1-3 mm. Heads of achenes cylindric, 9-16(-27) × 8-10 mm; achenes 1.6-2 × 1.8-2 mm, tomentose; beak persistent, lanceolate, 3.5-4.5 mm.
Small, scapose annual to 1 dm, thinly silky- tomentose; lvs 1–4 cm, ternate or biternate with narrow segments; sep greenish, ovate-lanceolate, persistent, accrescent to 5–6 mm; pet narrow, 4–8 mm, pale yellow, fading to whitish with pink veins; achenes (25–)35–70, widely spreading, forming a cylindric or ovoid bur (1–)1.5–2.5 cm, individually 5–7 mm, 3-locellar, the central chamber with a single seed, the 2 empty lateral chambers bulged-inflated on the upper side, the abrupt stiff beak longer than the body. Vernal ephemeral Eurasian weed, now widespread in w. U.S. and occasionally intr. with us, as in Io. and O. (Ceratocephalus t.)
