The New Zealand Plant Conservation Network

Species

Rorippa laciniata

Etymology

Rorippa: A latinized form of Rorippen, a Saxon vernacular name used by Euricius Cordus

Common Name(s)

cut-leaved bittercress

Current Conservation Status

2012 - Non Resident Native - Coloniser

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 - Non Resident Native - Coloniser
2004 - Not Threatened

Qualifiers

2012 - OL, SO
2009 - DP

Authority

Rorippa laciniata (F.Muell.) L.A.S.Johnson

Family

Brassicaceae

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Cardamine laciniata F.Muell.; Nasturtium laciniatum (F.Muell.) O.E.Schulz

Distribution

Indigenous. North Island, Hikurangi Swamp. Also Australia (New South Wales and Victoria)

Habitat

Lowland alluvial swamp forest - along muddy river banks under Coprosma scrub. Usually in places where water is ponded over winter

Features

Perennial tap-rooted herb, root stock ± woody, suberect to erect, producing one or more leafy, somewhat flaccid rosettes. Leaves 20–150 × 30–50 mm, mostly basal, narrowly elliptic, elliptic to broadly elliptic or rhomboidal, entire or irregularly and sometimes deeply toothed or lobed, lyrate-pinnatifid, or lyrate-pinnatisect, segments broadly to narrowly linear, often deeply toothed, with a terminal lobe and 1–4 pairs of narrow lobes, adaxially dark green to reddish-green, abaxially similar but lighter, glabrous; margin hairy, hairs up to 0.3 mm long; petioles 50–100 mm long, plano-convex, glabrous, margin narrowly winged; cauline leaves absent or few, similar to basal leaves but smaller and narrower. Inflorescence 10–30 or more flowered, 200–800 mm long, dark green to reddish green, glabrous, sprawling to ascending, often flaccid and supported by surrounding vegetation; flowers protogynous, slightly fragrant, up to 5.7 × 3.6 mm. Pedicels 9.2–12.2 mm long, erecto-patent at flowering, spreading at fruiting. Sepals 4, (2.3–)3.8–4.5 × 1.2–1.3 mm, linear-lanceolate, ± subulate, adaxially dark green, yellow-green to reddish green, glabrous; margin entire, thin, white; apex saccate, obtuse. Petals 4, 3.6–5.5 × 1.9–2.3 mm, oblong, white, flushed lavender at senescence, slightly longer than sepals, base cuneate, apex obtuse, claw 0.8–1.2 mm long. Stamens 4; filaments 2.5–4.0 mm long, white; anthers 0.6–0.8 × c. 0.4 mm, yellow, pollen yellow. Ovary 1.8–4.0 mm long, terete, green; style c. 0.5 mm long; stigma c. 0.6 mm diam., capitate to weakly bilobed. Siliques 15–46 × 1.3–1.8 mm, erect to spreading, linear, straight, ± terete, green, dark green to reddish green; valves with inconspicuous midrib fading toward apex; style remnant 0.5–0.8 mm long; seeds in 1 row per locule. Seed 1.3–1.4 × c. 0.9 mm, light orange-brown, slightly winged, testa punctate, spongy when fresh, mucilaginous.

Similar Taxa

Distinguished from Rorippa divaricata by the mostly basal, deeply cut leaves with distinctly hairy margins, few cauline leaves; petals > sepals, and coloured first white then flushing lavender at senescence, and by the seeds which are spongy when fresh, distinctly winged, with a punctuate rather than reticulate seed coat.

Flowering

October - January

Flower Colours

White,Yellow

Fruiting

November - February

Propagation Technique

Easily grown from fresh seed. Leaves edible. Not a particularly attractive plant.

Threats

About 100 plants are known so far from a single site that was discovered in January 2008. The only known population is within a reserve and there are no known threats.

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 19 Dec 2014