Corybas carsei
Common names
swamp helmet orchid
Biostatus
Native
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.
- 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 | Threatened – Nationally Critical | Qualifiers: CD, OL, TO
Category
Vascular
Structural class
Orchids
Flower colours
Red/Pink, White
Detailed description
Terrestrial orchid of restiad-dominated peat bogs. Plant 10–30 mm tall at flowering. Stem erect. Leaf 1–(2), 10–25–(30) mm long, green, sessile, ovate. Floral bract 1. Flower solitary, conspicuous, raised well above leaf. Perianth 8–10–(15) mm long, horizontal. Dorsal sepal spathulate from narrow arching claw, obtuse, hooded, slightly shorter than labellum, apex deeply cleft; base to mid section dark maroon-red, fading to yellow-green at apex, faintly striped maroon 2–6 times. Lateral sepals and petals linear 4–5–(8) mm long, white, more or less appressed to labellum. Labellum tubular, margins overlapping, entire, apex usually extending well beyond dorsal sepal; basal portion dark maroon-red, otherwise white, maroon colour extending as 8–(10) stripes, these almost reaching apex. Internal portion of labellum covered in prominent, retrorse, hair-like calli, forming a distinct band near labellum mouth, extending along mid-line and nerves for about half labellum length.
Similar taxa
Corybas rotundifolius, is similar but larger. The dorsal sepal lacks the cleft tip seen in C. carsei. The labellum is as long or slightly longer than the dorsal sepal, while the internal hairlike inward facing labellar calli are more prominent and extend nearly towards the column. Corybas rotundifolius flowers in mid-winter, and is more usually found in forested habits and on the margins of gumland scrub, only rarely does it grow within peat bogs.
Distribution
Possibly endemic (see Notes on taxonomy, below). New Zealand: North Island (from near Kaitaia south to Moanatuatua). Now known in New Zealand only from the Te Reao Arm of the Whangamarino Wetlands near Te Kauwhata, in the Huntly Basin, northern Waikato. Also Australia (New South Wales and Victoria, where it is now regarded as very uncommon).
Habitat
Known only from one site where it grows in open Schoenus / Empodisma sedge/wirerush vegetation, though it was formerly more common in several, now drained, Sporadanthus-dominated bogs.
Threats
Wetland drainage and plant collectors have contributed to the decline of this species in the past. The single remaining population is now mainly at risk through natural succession.
Detailed taxonomy
Genus
Family
Synonyms
Corysanthes carsei Cheeseman; Corybas matthewsii (Cheeseman) Schltr.; Corysanthes matthewsii Cheesem.; Anzybas carsei (Cheeseman) D.L.Jones et M.A.Clem.
Taxonomic notes
Considerable research is underway to investigate the validity of the segregate genera split from Corybas R.Br. by Jones et al. (2002). Whilst much of that work has yet to be published, on advice from Australian Orchidologists Peter Weston and Stephen Hopper (pers. comm., July 2011, November 2014), all of the segregate genera recognised for New Zealand by Jones et al. (2002) are returned to Corybas (see also Lyon 2014)
In addition the taxonomic status of Corybas carsei and the Australian C. fordhamii needs resolution. Morphologically there seems little to distinguish them. For now Corybas carsei is accepted as ‘possibly’ endemic. If these two species prove conspecific then C. carsei as the older name has priority.
Endemic taxon
Indeterminate
Endemic genus
No
Endemic family
No
Ecology
Flowering
September–(November)
Fruiting
December
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]
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely in uplands (non-wetlands).
Other information
Etymology
corybas: Helmet flower
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.
CORCAR
Chromosome number
2n = 36
Previous conservation statuses
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.
- 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.
2017 | Threatened – Nationally Critical | Qualifiers: CD, EF, OL, RR, TO
2012 | Threatened – Nationally Critical | Qualifiers: CD, EF, OL, RR
2009 | Threatened – Nationally Critical | Qualifiers: CD, RF, EF, OL
2004 | Threatened – Nationally Critical
Referencing and citations
References and further reading
Jones DL, Clements MA, Sharma IK, Mackenzie AM, Molloy BPJ. 2002. Nomenclatural notes arising from studies into the Tribe Diurideae (Orchidaceae). The Orchadian 13(10): 437–468. https://www.biodiversitylibrary.org/item/310769#page/2/mode/1up.
Lyon SP. 2014. Molecular systematics, biogeography, and mycorrhizal associations in the Acianthinae (Orchidaceae), with a focus on the genus Corybas. PhD Thesis, University of Wisconsin-Madison, USA. https://asset.library.wisc.edu/1711.dl/UAXO3VHO6P7EH8Y/R/file-19145.pdf.
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange (1 January 2005). Description adapted from Moore and Edgar (1970)
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.