Species

Pterostylis humilis

Etymology

Pterostylis: winged column
humilis: Lowest, dwarf, small, slight

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 - Not Threatened

Qualifiers

2012 - Sp

Authority

Pterostylis humilis Rogers

Family

Orchidaceae

Flora Category

Vascular - Native

NVS Species Code

PTEHUM

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

Orchids

Synonyms

None

Distribution

Endemic. North and South Islands. In the North Island known from the Central Volcanic Plateau and Mt Taranaki/Egmont, in the South Island in the west from north-west Nelson to about the Buller River

Habitat

Montane to subalpine in beech (Nothofagus Blume) forest and subalpine scrub. Often in deep drifts of leaf litter, or amongst mosses. Sometimes on bear ground or growing at the base of boulders.

Features

Terrestrial, tuberous, glabrous, spring to summer-green perennial herb, forming colonies through vegetative extension. Plant at flowering 45-50(-150) mm tall. Stem erect, smooth, dark green, to blue-green, immersed within a loose basal rosette of leaves until the fruiting ovary elongates the stem. Leaves erect to somewhat spreading, 3-4, margins entire, though usually undulose in the basal third, overtopping the flower; lamina 40-90 x 15-25 mm, dark green to blue-green, broadly elliptic to oblong, apex obtuse to broadly subacute, base gradually narrowing into a broadly winged sheathing petiole. Flower solitary, erect, dark green, white striped. Ovary mostly erect. Dorsal sepal 20 mm tall, erect then horizontal; apex shortly acuminate; lateral sepals diverging at a narrow angle, initially erect, apex acuminate to shortly caudate, overtopping galea. Petals almost as long as dorsal sepal, broad almost to apex. Labellum elliptic, shortly recurved, cucullate, scarcely protruding, apex acute, glabrous. Column slightly shorter than labellum; stigma prominent, broadly cordate, upward facing

Similar Taxa

Very close to P. venosa Colenso from which it differs by the prominent, upturned, heart-shaped, stigma, which is little longer than wide, and by the glabrous labellum surface.

Flowering

November - January

Flower Colours

Green,White

Fruiting

December - March

Propagation Technique

Difficult - should not be removed from the wild. Basic orchid mix consists of 2 parts medium coarse sand, ideally clean river sand; 2 parts soil, humus or leaf-mould; 1 part weathered sawdust or rotting wood; 1 part granulated bark. For Pterostylis shade of 50% and pots kept evenly moist.

Threats

Not Threatened but not very common either. May qualify for listing as Sparse.

Chromosome No.

2n = 44

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Not commercially available

Attribution

Fact Sheet prepared for NZPCN by P.J. de Lange 14 April 2007: Description adapted from Moore and Edgar (1970).

References and further reading

Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.

This page last updated on 31 Oct 2014