Classification
 Nomenclature
Scientific Name:
Pachycladon exile (Heenan) Heenan & A.D.Mitch. in Heenan et al., New Zealand J. Bot. 40: 559 (2002) – as exilis
Synonymy:
  • Ischnocarpus exilis Heenan, New Zealand J. Bot. 37: 46-49 (1999)
 Description

Perennial herb up to 10 cm tall; stems and rootstock slender. Radical leaves 7– 20 mm long, simple, densely covered with stellate hairs on petiole, lamina, and margin when young, becoming ± glabrous with age; early radical leaves often simple with few serrations, later leave s pinnatifid or pinnatisect, lobes in 2–4 opposite or subopposite pairs; lamina 4–9 × 1 .5–5 mm; petioles 3–14 × 0 .2–0.5 mm, channelled. Cauline leaves 1– 4, lower leaves similar to radical leaves, uppe r cauline leaves c. 3 × c. 0 .5 mm, linear, often with minute serrations. Inflorescences 4–10 cm long, with 3–10 flowers, peduncle at base c. 0.5 mm diam., racemose, glabrous or with sparse stellate hairs. Pedicels 8–12 × 0 .4–0.5 mm, glabrous. Peduncle, pedicels, and siliques with slight glaucous bloom. Sepals 1 .8–2.4 × 1 .0–1 .1 mm, ascending, oblong to elliptic, with sparse stellate hairs, green with pale margins, subacute. Petals 3 .0–5.0 × 0 .3–1 .0 mm, white, weakly obovate to obovate-spathulate, subacute, claw ± distinct; limb spreading. Stamens 4–6, of unequal lengths; filaments 1 .5–2.5 × c. 0.2 mm, linear; anthers 0 .4–0.7 mm long, yellow. Ovary at anthesis 2 .0–4 .0 × 0 .3–0.5 mm, terete, light brown or green-brown, glabrous; style 0.1–0.2 mm long, green; stigma c. 0.3 mm diam.; ovules 40–62. Siliques 15–25 × 0.7–1.0 mm, terete, often curved, glabrous; valves green in lower part, brown-green or light brown in the upper part. Seeds 0.6–0.9 mm long, short-oblong, pale brown, numerous and in one row in each locule. FL Oct–Nov; FT Oct Dec. Endemic.

[Reproduced from Molloy et al. (1999, New Zealand J. Bot. 37: 41–50, as Ischnocarpus exilis Heenan) with permission from The Royal Society of New Zealand.]

 Biostatus
Indigenous (Endemic)
 Bibliography
de Lange, P.J.; Norton, D.A.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Hitchmough, R.; Townsend, A.J. 2009: Threatened and uncommon plants of New Zealand (2008 revision). New Zealand Journal of Botany 47: 61–96. [Nationally Critical]
de Lange, P.J.; Norton, D.A.; Heenan, P.B.; Courtney, S.P.; Molloy, B.P.J.; Ogle, C.C.; Rance, B.D. 2004: Threatened and uncommon plants of New Zealand. New Zealand Journal of Botany 42(1): 45–76.
de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series. No. 22. [Nationally Critical]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Nationally Critical]
Heenan, P.B. 2009: A new species of Pachycladon (Brassicaceae) from limestone in eastern Marlborough, New Zealand. New Zealand Journal of Botany 47: 155–161.
Heenan, P.B.; Mitchell, A.D.; Koch, M. 2002: Molecular systematics of the New Zealand Pachycladon (Brassicaceae) complex: generic circumscription and relationships to Arabidopsis sens. lat. and Arabis sens. lat. New Zealand Journal of Botany 40(4): 543–562.
Molloy, B.P.J.; Edgar, E.; Heenan, P.B.; de Lange, P.J. 1999: New species of Poa (Gramineae) and Ischnocarpus (Brassicaceae) from limestone, North Otago, South Island, New Zealand. New Zealand Journal of Botany 37(1): 41–50.