Ranunculus pentandrus var. platycarpus

Annual, stems spreading to erect, 5–40 cm long, subglabrous to pilose. Leaves of juvenile plants broadly 3–5-lobed, adult leaves usually biternate to triternate, the lobes lanceolate to narrowly oblanceolate, entire or toothed, usually c. 1–2 cm long and wide overall; petioles mostly 1–5 cm long. Flowers 2–3 mm diam., sessile or subsessile in axils, pedicels elongating (to c. 2 cm) in fruit; sepals 3–5, elliptic to obovate, c. 2 mm long, pilose on back; petals 1 or 2, obovate to spathulate, slightly shorter than sepals, white; nectary attached at or slightly above middle, lobe semicircular to rhombic, free above midway, c. 0.2 mm long; stamens 3–5. Achenes usually 10–30, c. orbicular, 2.5–3.5 mm diam., almost flat, usually warped at maturity, with small tubercles scattered over the central half of the faces; beak triangular, c. 0.5 mm long; receptacle glabrous.  Flowers Jul.–Dec.