Cardamine caesiella Heenan

Perennial herb, single rosette or with short lateral branches. Leaves up to 90 mm long, simple or pinnatisect; lamina 1.8–45.0 × 1.8–32.0 mm, grey-green to blue-grey, coriaceous, glabrous or margin with spreading to patent hairs 0.3–0.4 mm long, petiole up to 27 mm long, sparsely hairy, hairs 0.3–0.4 mm long, spreading to patent. Terminal pinna 1.8–45.0 × 1.8–32.0 mm, simple, broadly ovate, broadly orbicular-deltoid; margin entire to shallowly sinuate, with 5–6 indistinct hydathodes; apex obtuse with an indistinct hydathode; base truncate or occasionally obtuse. Lateral pinnae absent or 1–2, 3.0–16.0 × 2.0–10.0, obovate, broadly elliptic, broadly ovate, or broadly elliptic-rhomboid; apex obtuse; base often oblique; petiolule 0.2–1.0 mm long. Cauline leaves similar to rosette leaves but smaller, narrower, pinnae bases attenuate to cuneate; terminal pinna up to 20.0 × 11.5 mm, often with 1–2 lateral teeth, lateral pinnae up to 10.5 × 3.5 mm. Inflorescence racemose, sometimes with lateral racemes, each raceme 3–12-flowered; peduncle up to 230 mm long, 0.3–1.6 mm diam. at base, spreading to ascending, glabrous. Pedicels 2.5–32.0 mm long, 0.3–0.9 mm diam., glabrous. Sepals 2.2–2.9 × 0.7–0.9 mm, elliptic-oblong, saccate, green to red-brown, sparsely hairy, hairs spreading to patent, margin white and membranous, apex obtuse, base truncate. Petals 4.9–5.6 × 1.9–2.4 mm, white, limb obovate; apex obtuse; base attenuate, tapering to a c. 0.5 mm long claw. Stamens 6; median filaments 4, 2.0–2.3 mm long; lateral filaments 2, 1.7–2.0 mm long; anthers 0.5–0.6 mm long, cream to pale yellow, when dehiscent held at a similar height to or slightly below the stigma. Ovary 1.9–2.5 mm long, 0.4–0.6 mm diam., ± terete, green, glabrous; ovules 15–26; style c. 1.0 mm long, ± terete; stigma 0.3–0.4 mm diam. Siliques 13.0–25.0 × 1.2–1.6 mm, glabrous, style 0.5–0.8 mm long; valves green to yellow-green at maturity and when dehiscent; replum 0.5–0.6 mm wide. Seeds 0.8–1.5 mm long, 0.8–1.0 mm wide, 0.4–0.5 mm thick, oblong to broadly oblong, henna-green to henna; wing absent.

Cardamine caesiella occurs on ledges and in crevices on limestone bluffs and rock outcrops.

Flowering November–December; Fruiting December.

The Manahune limestone outcrop and escarpment is a hotspot for vascular plant endemism, as two other limestone endemics occur there, Gentianella calcis subsp. manahune (Glenny 2004) and Ranunculus aff. stylosus (CHR 515131). Manahune is also a stronghold for the more widespread unnamed calcicole Geranium ‘Manahune’ (e.g., CHR 505532).