Plants of 1-8 or more rosettes, with ascending leaves. Leaves cartilaginous, orange-green, up to 32 cm or more long, once pinnate with 1-2 pairs of leaflets; sheath up to 54 × 17-8 mm; stipules simple, up to 27 × 1 mm, sometimes wanting, up to 6 mm apart at insertions; petiole up to 60 × 6, mostly shorter, concave, margins acute, sheath joint obscure, pulvinus mostly obscure, sometimes evident and up to 5 mm long; lamina ± obtrullate in outline; lowermost leaflet up to 220 × 5 mm with an apical spine up to 6 mm long, margin and midribs yellow to orange, up to 1 mm wide, the former often raised; marginal tubercles coarse, up to 0.15 mm wide, often forming a discontinuous series. Inflorescences narrow. Female inflorescences up to 40 cm long occasionally more,* with stems up to 250 × 10 mm, reddish brown; head up to 150 × 20 mm, more or less lanceolate in outline; compound umbels up to 22; lower bracts up to 100 mm long with a sheath up to 28 × 8 mm, stipules up to 12 × 1 mm and a simple lamina up to 75 × 3 mm, all segments ascending to appressed. Lower compound umbels up to 25 mm long with peduncles up to 6 × 1.4 mm, primary bracteoles usually wanting; up to 4 simple umbels with peduncles up to 8 × 1 mm, the innermost umbels often sessile, secondary bracteoles few up to 2 × 0.8 mm; a few accessory umbels in the bract axils. Up to 10 flowers per umbel with a few in the centre reduced; pedicels up to 2 × 0.9 mm; sepals up to 0.3 mm long; petals c. 1 × 0.6 mm, not inflexed and with a conspicuous red-brown median oil tube; staminodes up to 0.6 mm long with anthers up to 0.2 mm long; mature mericarps pale brown and glossy, up to 8 × 3.3 mm, each pair with 5/3 or 4/3 ribs; lateral ribs up to 0.5 mm wide; oil tubes orange, up to 6 on the commissure, 3-4 in the intervals, those in the ribs equal to or smaller than those in the intervals; styles up to 1.2 mm long. Male inflorescences up to 38 cm long with stems up to 150 × 6 mm, reddish brown; head up to 230 × 50 mm, narrow-ovate in outline; compound umbels up to 27; lower bracts up to 85 mm long with a sheath up to 30 × 4 mm, stipules up to 10 × 1 mm and a simple lamina up to 54 × 2 mm, segments ascending. Lower compound umbels up to 47 mm long with peduncles up to 23 × 1 mm, primary bracteoles usually wanting; up to 9 simple umbels with peduncles up to 16 × 0.9 mm, the innermost umbels often sessile or almost so; secondary bracteoles 6-7, up to 1.5 × 0.3 mm; a few simple to partly compound accessory umbels in the bract axils. Up to 12 flowers per umbel; pedicels up to 3 × 0.4 mm; sepals up to 0.3 mm long; petals c. 1.1 × 0.75 mm, not inflexed and with a conspicuous redbrown median oil-tube; stamens c. 1.75 mm long with filaments c. 1.25 × 0.1 mm and anthers c. 0.5 × 0.4 mm. *On a recent visit to Stewart Island Webb (pers. comm.) observed some infructescences up to 80 cm and more rarely 100 cm in length.

Folia pinnata, usque ad 32 cm longa; foliolis 1-2 jugis, cartilagineis, tuberculatis; stipulis simplicibus, brevioribus quam petiolis vel obsoletis; petiolis brevibus. Inflorescentia elongata, feminea usque ad 40 cm longa, mascula usque ad 38 cm longa; bracteis trifoliatis, adscendentibus. Mericarpium circa 8 mm longum, 3.5 mm latum, stylo circa 1.2 mm longo, jugis 5, 4 vel 3, circa 0.5 mm latis, vittibus 3-4 ad valleculas.