Thelymitra formosa
Common names
sun orchid
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Orchids
Flower colours
Blue, Violet/Purple
Detailed description
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 × 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 a very robust orchid which is usually found as solitary plants, though on occasion it may found quite substantial colonies.
Distribution
Endemic. New Zealand: North Island, South Island, Stewart Island/Rakiura.
Habitat
Mainly found in lowland to montane wetlands, scrub and open forest. Occasionally colonises roadside banks.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | At Risk – Naturally Uncommon | Qualifiers: EF, Sp
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.
Detailed taxonomy
Family
Orchidaceae
Taxonomic notes
There is some uncertainty over the application of the name Thellymitra 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.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
November–January
Fruiting
December–March
Propagation technique
Difficult. Should not be removed from the wild
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FAC: Facultative
Commonly occurs as either a hydrophyte or non-hydrophyte (non-wetlands).
Other information
Etymology
thelymitra: Woman’s hat
Manaaki Whenua Online Interactive Key
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
Previous conservation statuses
2017 | At Risk – Naturally Uncommon | Qualifiers: EF, Sp
2012 | At Risk – Naturally Uncommon | Qualifiers: EF, Sp
2009 | At Risk – Naturally Uncommon | Qualifiers: DP, EF
2004 | Sparse
Referencing and citations
References and further reading
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Rolfe JR, de Lange PJ. 2010. Illustrated guide to New Zealand sun orchids, Thelymitra (Orchidaceae). Jeremy Rolfe, Wellington, NZ. 57 p.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 14 April 2007. Description subsequently published in Rolfe & de Lange (2010).
NZPCN Fact Sheet 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)