Cardamine bisetosa Heenan

Perennial herb, single rosette or with lateral branches. Leaves up to 70 mm long, pinnatisect; lamina 10.0–35.0 × 7.0–15.0 mm, green, membranous, glabrous to sparsely hairy on abaxial surface, sparsely to moderately hairy on adaxial surface, margin and petiole; hairs 0.2–0.5 mm long, spreading to patent; hydathode in leaflet axil, c. 0.1 mm long; petiole up to 36 mm long, with sparse, weakly spreading hairs. Terminal pinna 2.6–7.0 × 3.2–10.0 mm, simple, broadly orbicular to broadly reniform; margin usually shallowly lobed, with 2–4 distinct hydathodes; apex obtuse with a distinct hydathode; base cordate, truncate or occasionally obtuse. Lateral pinnae 2–6, 2.0–5.0 × 1.8–5.8 mm, orbicular to broadly elliptic-orbicular; margin usually shallowly lobed, with 1–2 distinct hydathodes; apex obtuse with a distinct hydathode; base cordate, truncate or obtuse; petiolule 0.5–5.3 mm long. Cauline leaves similar to rosette leaves but smaller, narrower, with fewer lateral pinnae, pinnae bases attenuate to cuneate; terminal pinna up to 4.0 × 4.2 mm, lateral pinnae up to 3.5 × 2.5 mm. Inflorescence corymbose to corymbose-racemose, with lateral corymbs, each corymb 1–3-flowered; peduncle up to 150 mm long, 0.5–0.8 mm diam. at base, spreading to ascending, sparsely to densely hairy, occasionally glabrous. Pedicels 1.0–25.0 mm long, 0.2–0.3 mm diam., sparsely to densely hairy, hairs appressed and retrorse. Sepals 1.2–1.6 × 0.6–0.8 mm, elliptic-oblong, saccate, green to red-brown, sparsely hairy, hairs spreading to patent, margin white and membranous, apex obtuse, base truncate. Petals 2.7–3.5 × 0.7–0.9 mm, white, limb narrowly obovate; apex obtuse; base attenuate, tapering to a c. 0.2 mm long claw. Stamens 6; median filaments 4, 1.8–2.3 mm long; lateral filaments 2, 1.2–2.0 mm long; anthers 0.3–0.4 mm long, cream to pale yellow or maroon, when dehiscent held at a similar height to or slightly below the stigma. Ovary 2.5–2.7 mm long, 0.3–0.4 mm diam., ± terete, green, moderately to densely hairy; hairs <0.1 mm long, retrorse; ovules 14–18; style c. 0.2 mm long, ± terete; stigma 0.2–0.3 mm diam. Siliques 13.0–25.0 × 0.9–1.2 mm, hairs moderate to dense, appressed and retrorse, style 0.4–2.2 mm long; valves yellow-green to green-brown at maturity and when dehiscent; replum 0.2–0.3 mm wide. Seeds 1.0–1.3 mm long, 0.6–1.0 mm wide, 0.2–0.25 mm thick, oblong to broadly oblong, henna-green to henna; wing absent.

Cardamine bisetosa occurs on limestone, usually in shade at the margin of sinkholes, cliffs, and ravines.

Flowering November–January; Fruiting November–January.

Three specimens from Titapu, on the western flank of the Ruahine Range, have glabrous to very sparsely hairy leaves and stems. These differ from specimens to the east of the Ruahine Range that have sparsely to moderately hairy leaves and stems.