Corybas macranthus
Common name
silver-back spider orchid
Synonyms
Corysanthes macrantha (Hook.f.) Hook.f.; Nematoceras macranthum Hook.f.
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.
NEMMAC
Chromosome number
2n = 36
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 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
Distribution
Endemic. North, South. Stewart, Chatham, Auckland and Campbell Islands
Habitat
Lowland to subalpine (up to 1200 m a.s.l.) usually in damp, shaded to well-lit seepages, or in shaded sites under tall forest or associated with rock overhangs (then often in very dry sites). Favouring base-rich substrates such as calcareous mudstones, siltstones, limestones, dolomite or marble; also on basalt and basaltic-andesites, and soils derived from these.
Features
Terrestrial, tuberous, spring to summer green perennial forming dense colonies. Plant at flowering 40-100 mm tall. Leaf solitary, distinctly petiolate, petiole hyaline to white, more or less fleshy up to 60 mm long, suberect, ascending; lamina firmly fleshy, up to 40 x 40 mm, mostly green flecked or spotted with purple, or dark green above, silvery green to white beneath, orbicular to oblong-oval, apiculate, base rounded. Floral bract minute, < ovary, narrowly deltoid, initially closely sheathing spreading at flower anthesis. Dorsal sepal mostly shorter than labellum, hyaline yellow-green to greenish-white flecked with crimson or completely wine red, rather long and narrow-lanceolate, acute to shortly acuminate, arching over tubular portion of labellum; lateral sepals dark pink to crimson, filiform, greatly exceeding labellum. Petals similar to lateral sepals but usually much shorter. Labellum completely dark maroon-black or wine red, or dark maroon-black with a greenish throat, auriculate at base, lamina abruptly deflexed, funnelform, broadly expanded all round, margin minutely denticulate with a median apiculus, inner surface rough with short, sharp, retrorse papillae
Similar taxa
The stout, fleshy leaf which is usually held up above the flower, and widely flaring trumpet shaped dark maroon-black or wine red labellum, and very narrowly lanceolate dorsal sepal distinguish this species from all except the little known Corybas papillosus. Corybas papillosus differs from C. macranthus mainly by its bicoloured labellum (dark red to purple-red in the upper half, pale pink grading through to whitish in the lower half).
Flowering
September - January
Flower colours
Red/Pink, Yellow
Fruiting
October - February
Propagation technique
Difficult - should not be removed from the wild. Can be grown in 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. Many Corybas thrive when more leaf-mould is added, and the plants grown in 50-70% shade, in the cooler, darker end of the shade-house, in pots kept moist throughout the growing period.
Etymology
corybas: Helmet flower
Where To Buy
Not commercially available
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.
Recently Lehnebach (2016) has made three combinations for those Nematoceras lacking valid names in Corybas. This action now enables the full transfer of Nematoceras back to Corybas. However, as of writing, a formal publication rejecting the segregation of Corybas by Jones et al. (2002) has yet to be published. Lehnebach cites an unpublished PhD (Lyon 2014) that indicates this move is imminent.
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
Jones, D.L.; Clements, M.A.; Sharma, I.K.; Mackenzie, A.M.; Molloy, B.P.J. 2002: Nomenclatural notes arising from studies into the Tribe Diurideae (Orchidaceae). The Orchadian 13: 437-468.
Lehnebach, C. 2016: New combinations and a replacement name for three New Zealand spider orchids (Corybas). The New Zealand Native Orchid Journal 139. 4-5.
Lyon, S. P. 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.
Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Corybas macranthus Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/corybas-macranthus/ (Date website was queried)