The New Zealand Plant Conservation Network

Species

Pachycladon exile

Etymology

exile: From the Latin exile (thin, slender, feeble, meager)

Common Name(s)

None known

Current Conservation Status

2012 - Threatened - Nationally Critical

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Threatened - Nationally Critical
2004 - Threatened - Nationally Critical

Qualifiers

2012 - CD, OL
2009 - CD, OL

Authority

Pachycladon exile (Heenan) Heenan et A. Mitch.

Family

Brassicaceae

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Ischnocarpus exilis Heenan, Pachycladon exilis (Heenan) Heenan et A.D.Mitch. orth.var.

Distribution

Endemic. South Island, South Canterbury and North Otago. Formerly present in a number of sites along the Waitaki River and at Cape Wanbrow. Now apparently confined to a single site near Awahokomo Creek.

Habitat

A species apparently favouring dry, exposed limestone rock and associated rendzina soils. it seems to require open ground to thrive and is intolerant of much competition.

Features

Slender, grey-green, thread-like perennial herb, up to100 mm tall. Basal leaves 7-20 mm long, simple, initially densely invested with stellate hairs, becoming glabrescent with age; early basal leaves elliptic, entire or with a few blunt serrations, later leaves pinnatifid to pinnatisect, lobed 2-4 times in opposite to subopposite pairs; lamina, 4-9 x 1.5-5 mm. Stem leaves 1-4, lower ones similar to basal leaves, upper 3 x 0.5 mm, linear, minutely serrated. Inflorescences racemose, 40-100 mm long, glaucescent, 3-10-flowered. Pedicels 8-12 x 0.4-0.5 mm, glabrous. Sepals 1.8-2.4 x 1-1.1 mm, green with pale margins, ascending, oblong to elliptic, subacute. Petals 3-5 x 0.3-1 mm, white, obovate to obovate-spathulate, subacute. Stamens 4-6, anthers green to green-brown. Style 0.1-0.2 mm, green. Siliques 15-25 x 0.7-1 mm, green to brown-green, terete, usually curved, glabrous. Seeds 0.6-0.9 mm, pale brown, short-oblong.

Similar Taxa

Similar to Pachycladon cheesemanii Heenan et A.D.Mitch. but smaller in all parts and with an ovary circular (terete) in cross-section.

Flowering

October-November

Flower Colours

Green,White

Fruiting

October-December

Propagation Technique

Easily grown from fresh seed. A short-lived, fairly non-descript plant which does best in a sunny exposed situation, growing within a fertile, free draining, soil. This is more of a plant for a specialist as it is not particularly attractive, and very prone to fungal diseases and insect damage. The foliage is edible.

Threats

Threatened by the very small number (< 50 individuals) of plants known from the wild. These plants are confined to a single limestone outcrop where they are at risk from the spread of weeds such as Pilosella and Cocksfoot (Dactylis glomerata), and erosion caused by excessive rabbit browsing pressure on the associated rock outcrop vegetation.

Chromosome No.

2n = 20

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 17 Apr 2014