Stout tufted herb with simple or branched stock, forming clumps up to ± 25 cm. diam., and 4 dm. tall. Lvs 3-pinnatisect, lamina 6-10 cm. long. Sheath up to c. 5 × 2.5 cm., ribbed; margins membr. Stipules 2.5-5 cm. long, tapering from ± 1mm., on very short ligules, pungent. Petioles up to c. 15 cm. long, stout, rigid, concavo-convex; margins thickened. Internodes up to 15 mm. long. Primary pinnae (4)-6-(8) pairs; secondary 2-4 pairs; tertiary very slender to almost filiform, ± 2-4 cm. × 1 mm., pungent. Stems of female plants stout, up to 3 dm. long including infl. up to c. 15 cm. long. Bract-sheaths thin, ± 4 × 1 cm., including short ligule; stipules acicular, up to 1 cm. long; lamina 2-3-pinnate, up to c. 4 cm. long, on petiole ± 10 mm. long. Umbels ∞ forming a ± globose panicle ± 8-10 cm. diam. Primary rays up to c. 4 cm. × 1 mm. grooved. Umbellules many, up to c. 3 cm. diam. on rather slender rays. Fr. narrow, ± 3 mm. long; mericarps 5-(4)-winged.

2n = 22