The New Zealand Plant Conservation Network

Species

Pterostylis auriculata

Etymology

Pterostylis: winged column
auriculata: small-eared

Common Name(s)

Greenhood

Current Conservation Status

2012 - At Risk - Naturally Uncommon

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 - At Risk - Naturally Uncommon
2004 - Data Deficient

Qualifiers

2012 - Sp

Authority

Pterostylis auriculata Colenso

Family

Orchidaceae

Flora Category

Vascular - Native

NVS Species Code

PTEAUR

Structural Class

Orchids

Synonyms

None

Distribution

Endemic. North, South, Stewart and Chatham Islands. In the North Island recorded so far from Kapiti Island. In the South Island known from south-east Otago (Catlins Coast) and Southland. Recorded in November 2008 from one site on Rangiauria (Pitt Island) in the Chatham Islands group

Habitat

Coastal to montane.(up to 521 m a.s.l. on Kapiti Island). Favouring permanently damp, heavily shaded, sites in dune forest in the Catlins, south-eastern South Island, and under dense kamahi (Weinmannia racemosa) and mapou (Myrsine australis) on Kapiti Island. On the Chatham Islands it grows with Pterostylis banksii and P. silvicultrix in mixed matipo (Myrsine chathamica), Ribbonwood (Plagianthus regius subsp. chathamicus), Tarahinau (Dracophyllum arboreum) forest.

Features

Terrestrial, glabrous, tuberous summer-green perennial. Plant erect, all parts distinctly glossy, up to 380 mm tall. Stems bright-red to reddish green. Leaves 4, all cauline, of more or less equal length, usually overtopping the galea, 125-180 x 10-12 mm, pale-green to dark green, lanceolate, distinctly acuminate, arching with apices drooping, widest near sessile sheathing base, midrib prominent, reddish. Flower solitary, narrowly erect, green with a reddish tint. Ovary slender, 10 mm long, reddish, linear-ellipsoid. Dorsal sepal 15-18 mm long, narrowly ovate, shortly acuminate, lateral sepals erect, narrowly divergent, sinus large, apices caudate, 8-9 mm long, overtopping galea, spreading, narrow and more or less falcate caudae. Petals narrowly ovate, shortly acuminate. Labellum 10 x 2.3-4.6 mm, dark-red, linear-oblong, distinctly arched and tapering toward the truncate or slightly retuse to emarginate apex, midrib prominent, keeled below, deeply depressed above, somewhat twisted, with 4 flexuous lateral veins on each side; basal callus wide, shortly curved, and coarsely fimbriate. Column slender about as long as labellum, wings prolonged upwards as subulate apices nearly 2.3 mm long, narrow auriculate; auricles 4.5 mm long, with the apices closely and finely ciliate.

Similar Taxa

Pterostylis banksii has narrow, more upright leaves and larger flowers; P. australis has short sepals and broad upright leaves; both lack the tapered labellum. The various forms included in P. montana are smaller plants, with oblong apically twisted labella. Distinguished from P. silvicultrix by longer, narrower, arching leaves; longer dorsal and lateral sepals; lateral sepals which are not twisted or turned forwards, and straight rather than twisted labellum.

Flowering

October - November

Flower Colours

Green,Red / Pink

Fruiting

December

Propagation Technique

Difficult - should not be removed from the wild.

Threats

Seemingly uncommon and probably biologically sparse, but known habitats are in protected areas.

Chromosome No.

2n = 44

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 24 Jan 2015