Species

Myosotidium hortensia

Etymology

Myosotidium: myosotis-like

Common Name(s)

Chatham Island Forget-me-not, Kopakopa, Kopukapuka

Current Conservation Status

2012 - Threatened - Nationally Vulnerable

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 Vulnerable
2004 - Threatened - Nationally Endangered

Qualifiers

2012 - CD, IE
2009 - CD, IE, Inc, RR

Authority

Myosotidium hortensia (Decne.) Baill.

Family

Boraginaceae

Flora Category

Vascular - Native

NVS Species Code

MYOHOR

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Myosotis hortensia Decne, Cynoglossum nobile Hook.f., Myosotidium nobile (Hook.f.) Hook.f.; Myosotidium hortensium (Decne.) Baill. orth.var.

Distribution

Endemic to the Chatham Islands. Found on Chatham (Rekohu), Pitt, South East, Mangere and most of the smaller islands, islets and some rock stacks.

Habitat

Coastal cliffs, rock outcrops, sandy and rocky beaches just above the strand zone and coastal forest openings.

Features

Robust, perennial herb, forming patches up to 1 m tall by 1.0–1.5 m diameter. Root stock stout, cylindric, rather fleshy, where emergent covered in numerous leaf scars, becoming woody with age. Petioles 0.1–0.5 m long, grooved above, channelled below. Lamina of basal leaves up to 0.4 m across, dark green to yellow-green, broadly ovate-cordate to reniform, thick, fleshy to coriaceous; upper surface glossy, glabrous; lower surface paler, minutely and evenly covered in retrorse hairs; margins entire; veins prominent, indented above, elevated below. Inflorescences lateral corymbose cymes, somewhat woody at base, with stem leaves; lower stem leaves similar to basal leaves, upper stem leaves smaller, oblong to broadly lanceolate or elliptic. Cymes 100–200 mm diameter, pedicels 10–15 mm long. Calyx lobes 5, 1.8–4.5 × 2.0–2.5 mm, broadly elliptic, covered in appressed hairs, apex obtuse, margin entire. Corolla 12–15 mm diameter, dark blue to pale blue, often flushing purple with age, occasionally white; lobes 5, 4.0–4.5 × 5.0–6.0 mm, orbicular, rounded, spreading, overlapping, apex obtuse; tube 2 mm long, throat partially occluded by 5 fleshy protuberances. Filaments c. 0.5 mm long, inserted near throat; anther included, 1.0–1.2 mm long. Ovary 4-lobed, style 0.7–1.0 mm long, stigma capitate. Fruit a nutlet, 10–15 mm diameter, brown to black, winged around margin; seed obovate, 7.5–9.0 mm long, testa black-brown..

Similar Taxa

A distinctive and easily recognised species with large, glossy green leaves and large blue-flowered inflorescences.

Flowering

September - November

Flower Colours

Blue,Violet / Purple

Fruiting

October - May

Propagation Technique

Easy to grow provided the root stock is kept moist. It will not tolerate drought. It also dislikes humidity. Does best in a rich, well fertilised, peaty soil on the south-side of a building, or near a dripping tap. Also does well in partial shade under trees. Avoid competition from other plants. Seed germinates well if fresh but will not store long. A white-flowered form is occasionally grown.

Threats

Formerly abundant around the coasts and islets, the range of M. hortensia has been significantly reduced to scattered remnants by farming, competition from marram grass (Ammophila arenaria) and the depredations of feral animals, such as cattle, horses, sheep, possums, pigs, rats and weka who trample, uproot and browse plants. Possums, rodents, and weka are serious predators of flowers and fruits. Weed encroachment, especially by marram grass, has eliminated this species from ost of its former dune habitat. Removing whole plants for private use in gardens is an on going problem for the more accessible populations. Coastal development destroyed the only known white-flowered wild plants, and remains a potential threat elsewhere.

Chromosome No.

2n = 40-42

Endemic Taxon

Yes

Endemic Genus

Yes

Endemic Family

No

Where To Buy

Commonly available from most commercial and specilaist native plant nurseries.

Attribution

Fact Sheet prepared for NZPCN by P.J. de Lange 1 February 2008. Description based on de Lange et al. (2010).

References and further reading

de Lange, P.J.; Heenan, P.B.; Norton, D.A.; Rolfe, J.R.; Sawyer, J.W.D. 2010: Threatened Plants of New Zealand. Canterbury University Press, Christchurch.

This page last updated on 19 Dec 2014