The New Zealand Plant Conservation Network

Species

Pterostylis brumalis

Etymology

Pterostylis: winged column

Common Name(s)

kauri greenhood, winter greenhood

Current Conservation Status

2012 - Not Threatened

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 - Not Threatened
2004 - Not Threatened

Authority

Pterostylis brumalis L.B.Moore

Family

Orchidaceae

Flora Category

Vascular - Native

NVS Species Code

DIPBRU

Structural Class

Orchids

Synonyms

Diplodium brumale (L.B.Moore) D.L.Jones, Molloy et M.A.Clem.

Distribution

Endemic. North Island from Te Paki to Kawhia Harbour and the northern Kaimai Ranges. Most common north of Thames and Auckland City.

Habitat

Coastal to lower montane. Virtually confined to forests dominated by kauri (Agathis australis (D.Don). Lindl.) where it prefers shaded sites, and usually grows in kauri leaf litter and leaf mould, often directly beneath the trunks of this species. It may also grow in gumland scrub but usually then only in association with rotting kauri stumps or subfossil kauri leaf and gum deposits.

Features

Terrestrial, colony forming, perennial herb. Plants at flowering up to 200 mm tall. Stem bright green often tinged with red, slender, terete, smooth; internodes usually < leaves. Petiolate leaves in separate loose rosettes or at the base the lower part of flowering stem; petiole distinct, up to 10 mm long; leaf lamina 5-12 x 5-12 mm, bright green or green, ovate-orbicular, apex subacute, upper leaf surface smooth. Cauline leaves 2-6, usually closely spaced and aggregated toward top of stem, subsessile to sessile, the lower pair transitional in shape between rosette and mid to upper cauline leaves, 15-40 x 2-8 mm, bright green to green, linear-lanceolate or narrow-elliptic, uppermost leaves usually overtopping ovary but usually falling short of the galea. Flower 1(-2) erect, most white with narrow dark green stripes. Dorsal sepal 15-30 mm tall, apex acuminate, usually down-curved; lateral sepals diverging at a wide angle to form a U or a wide W shape when viewed from the front, the sinus distinctly jugate in side view, tips long-caudate and much overtopping galea. Petals almost as long as dorsal sepal, with a broad, more or less horizontal marginal strip exposed . Labellum narrow-triangular, arched and protruding, apex subacute. Column shorter than labellum; stigma elliptic, slightly prominent.

Similar Taxa

Very distinctive and not easily confused with the other Diplodium species. The flower has a very strongly incurved dorsal sepal with the petals held horizontally thus imparting a distinctive cobra-hooded appearance. The prominent jug-shaped sinus of the lateral sepals is shared with D. alveatum (Garnet) D.L.Jones et M.A.Clem and D. trullifolium ((Hook.f.) D.L.Jones, Molloy et M.A.Clem.) but is absent from D. alobulum (Hatch) D.L.Jones et M.A.Clem. From all these species D. brumalum is separated by the linear-lanceolate or narrow-elliptic mid to upper stem leaves which tend to be aggregated towatd the stem apex. Ecologically D. brumalum is restricted to kauri forest.

Flowering

June - October

Flower Colours

Green,White

Fruiting

July - November

Propagation Technique

Difficult - should not be removed from the wild

Threats

Not Threatened

Chromosome No.

2n = 50

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Minute seeds are wind dispersed (Thorsen et al., 2009).

This page last updated on 13 Nov 2014