Glabrous perennial, very occasionally rhizomatous, with an erect succulent tuberculate stem to 30 cm high, rarely more, to 10 cm thick, rarely branching; tubercles in 5–8 spiralled series, rhomboid to about 15 × 12 mm, scarcely prominent, bearing the leaves at their apices.Leaves subsessile; lamina to 12(21) × 1.3(3) cm, linear lanceolate, apiculate at the apex, tapering to the base, entire.Cymes in axillary and terminal 1–3-branched umbels produced on slender leafy branches to 20 cm long arising from the tubercle axils with primary rays to 8 cm long, each forking many times.Bracts sessile, c. 3 × 2–3 cm, deltoid, apex acuminate, base subcordate, the bracts below the umbel larger and more leaf-like.Cyathia on peduncles 2–5 mm long, 5 × 12 mm with cup-shaped involucres; glands 4, or 5 on the central cyathium of the umbel, c. 1.5 × 4 mm, transversely elliptic, outer margin with 3–6 finger-like processes 1–2 mm long which branch and rebranch at the tips, terminating in minute knobs, purplish-red, rarely green; lobes 2.5 × 2.5 mm, subquadrate, margin deeply toothed, minutely puberulous.Male flowers: bracteoles fan-shaped, laciniate, feathery; stamens 8 mm long.Female flower: ovary pedicellate; styles c. 4 mm long, joined to c. halfway with spreading thickened minutely bifid apices.Capsule on an erect pedicel c. 1 cm long, 8 × 11 mm, subglobose, 3-lobed, with 6 longitudinal ridges when dry.Seeds 4.2 × 3.8 mm, subglobose, apex very obtuse, surface obscurely wrinkled, yellowish-grey.
