Thelymitra formosa
Common name
sun orchid
Family
Orchidaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Orchids
NVS code
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.
THEFOR
Chromosome number
2n = 40
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | At Risk – Naturally Uncommon | Qualifiers: EF, Sp
Previous conservation statuses
2009 | At Risk – Naturally Uncommon | Qualifiers: DP, EF
2004 | Sparse
Distribution
Endemic. North, South and Stewart Islands
Habitat
Mainly found in lowland to montane wetlands, scrub and open forest. Occasionally colonises roadside banks.
Features
Very stout, robust, usually solitary (sometimes colonial) orchid which at flowering is up to 0.8 m tall. Stem dark red-green or dark green (sometimes glaucous) stout, smooth. Leaf 100-400 x 10-20 mm, linear-lanceolate to lanceolate, usually dark green to red-green, channelled and finely ridged, rather fleshy (almost succulent) and thick, sheathing high up stem. Inflorescences 10-15-flowered. Perianth 9-13 mm long, light to dark blue, without stripes or spots. Sepals, petals and labellum similar, all narrowly-obovate. Column-arms flattened, more or less channelled, with yellow or orange fringes and cilia arising from margins, each arm projecting from inner face of side lobule, usually standing much taller than anther; post anther lobe shorter than anther, erect, margins yellowish red and more or less thickened into finger-like callii; side lobules taller than anther, pinkish or yellowish, fleshy, with subulate erect projections on margins and with similar or more elongated tubercles across the surface.
Similar taxa
A very distinctive and singular species of Thelymitra. It has no obvious close relatives though sterile plants or those in bud have some similarity to T. ixioides Sw., from which they can be distinguished by their smooth rather than finely rough stems and overall dark-green to reddish green, rather than somewhat glaucous-green to silvery red-green leaves. When in flower the combination of pale to dark blue unspotted to striped flowers, distinctively flattened yellow or orange fringed/ciliate column-arms which project from the inner face of the side lobule are especially diagnostic of T. formosa. Thelymitra formosa is very robust orchid which is usually found as solitary plants, though on occasion it may found quite substantial colonies.
Flowering
November - January
Flower colours
Blue, Violet/Purple
Fruiting
December - March
Propagation technique
Difficult. Should not be removed from the wild
Threats
An apparently naturally uncommon, biologically sparse species. Based on old herbarium specimens it does not appear to have ever been common at any particular location.
Etymology
thelymitra: Woman’s hat
Where To Buy
Not commercially available.
Notes on taxonomy
There is some uncertainty over the application of the name T. formosa - the type suite is largely another species T. hatchii L.B.Moore so further work on the status of plants referred to by the New Zealand Flora Series, Vol. II as T. formosa is needed. Description adapted from: Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 14 April 2007. Description subsequently published in Rolfe & de Lange (2010).
References and further reading
Rolfe, J.R.; de Lange, P.J. 2010: Illustrated guide to New Zealand sun orchids, Thelymitra (Orchidaceae). Jeremy Rolfe, Wellington.
Citation
Please cite as: de Lange, P.J. (Year at time of access): Thelymitra formosa Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/thelymitra-formosa/ (Date website was queried)