Rather stout tufted plant up to 4 dm. tall. Lvs up to ± 25 cm. long, us. shorter, including sheath ± 6·5 × 1 cm., with smooth margins. Stipules stiff, almost capillary, up to 3 cm. long, pungent; petioles up to 8 cm. × 5 mm., flattened, smooth or nearly so; internodes ± 25 mm. long, midrib stout, wings narrow. Pinnae 4-10 pairs, up to 8 cm. × 2-4 mm., ascending, in one plane; margins thickened, cartilaginous. Stems of male plants 30-40 cm. long including panicle. Bract-sheaths much wider than in , lamina pinnate. Umbels several to many, forming an open panicle ± 10 cm. diam., on rather stout short rays; umbellules small on 10-15 short rays. Stems of female plants similar to those of male, infl. c. 15 cm. long. Bract-sheaths ± 2 cm. × 5-(10) mm., rather thin; stipules very narrow, c. 1 cm. long, on short ligules; lamina with 1-2 pairs of lflts, terminal lflt up to c. 15 mm. long. Umbels rather distant; rays ± 5 cm. long. slender, us. many. Involucral bracts narrow-linear, ± 1 cm. long. Umbellules ± 1 cm. diam.; rays ∞, up to 10 mm. long. Fr ± 3-4-(5) mm. long; mericarps 3-5-winged.

Leaf rosettes up to 20 cm diameter in groups of 10 or more. Leaves coriaceous, yellow-green, up to 23 cm long, mostly 6—7 pairs of leaflets sometimes more, more or less in one plane; sheath up to 60 × 15-6 mm, sheath joint usually evident; stipules up to 40 × 1 mm, petiole up to 80 × 4 mm, flat to concave above, margins rounded, pulvinus evident up to 5 mm long; lamina ± rhombic in outline, lowermost leaflet up to 65 × 3—3.5 mm, apex acute with a spine up to c. 2 mm long, midrib obscure, marginrib c. 0.2 mm wide, veins not or slightly raised. Inflorescences of broad type. Female inflorescence up to 400 mm long, with a stem 300 × 5.5 mm, yellow to brown, head 100 × 90 mm, more or less obdeltate in outline; compound umbels up to 14, usually arranged in 2 - 3 whorls, the terminal umbel larger than the lower laterals; lower bracts c. 55 mm long with a sheath c. 23 × 6 mm, stipules, and 2 pairs of leaflets; upper bracts smaller and simple with stipules. Lower compound umbels up to 80 mm long with peduncles up to 60 × 1 mm, primary bracteoles simple, up to 10 × 0.5 mm: simple umbels up to 7 with peduncles up to 16 × 1 mm; secondary bracteoles simple up to 6 × 0.5 mm; up to 12 flowers per umbel with pedicels up to 3 × 0.2 mm. Sepals up to 0.6 mm long; petals up to 1.2 × 0.6 mm, not inflexed; staminodes up to 0.3 mm long. Mericarps pale brown, dull, up to 4.2 × 1.6 mm, with a style up to 1.3 mm long; lateral ribs up to 0.3 mm wide. Male inflorescence up to 300 mm long, with a stem 170 × 4 mm, yellow; head 130 × 90 mm, ovate to ± circular in outline; compound umbels up to c, 10 in 2 to 3 whorls, the terminal umbel larger than the lower laterals; bracts similar to those of the female; lower compound umbels up to 90 mm long with peduncles up to 70 × 2 mm; primary bracteoles up to 15 × 1.5 mm; up to 15 simple umbels with peduncles up to 10 × 1 mm; secondary bracteoles up to 5 × 0.2 mm; up to 15 flowers per umbel with pedicels up to 3 × 0.1 mm. Sepals up to 0.6 mm long; petals up to 1.5 × 1 mm, not inflexed; stamens up to 2 mm long.

2n = 22