Species

Caladenia atradenia

Common Name(s)

None Known

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 - Sparse

Qualifiers

2012 - EF, Sp

Authority

Caladenia atradenia D.L.Jones, Molloy et M.A.Clem.

Family

Orchidaceae

Flora Category

Vascular - Native

NVS Species Code

CALATR

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

Caladenia carnea var. minor f. calliniger Hatch nom. illeg., Caladenia calliniger Matthews nom. nud., nom. illeg., Stegostyla atradenia (D.L.Jones, Molloy et M.A.Clem.) D.L.Jones et M.A.Clem.

Distribution

Endemic

. North and northern South Island.

Habitat

Coastal to montane

(0-1000 m a.s.l.). Favouring infertile substrates, especially clay podzols and pumice soils, where ti may be found in the open or more usually in thick leaf litter under Kunzea ericoides (A.Rich.) Joy Thomps. and Leptospermum scoparium J.R.Forst. et G.Forst. shrubland, or in secondary regrowth. Also known from pine plantations and from geothermal areas in low scrub. Despite its colourful flowers its tendency to grow as solitary or small scattered, somewhat diffuse populations means that it is easily overlooked, even in sites where it is well known.

Features

Tuberous, terrestrial orchid growing as solitary plants or in small groups of 2-10 individuals, all vegetative parts markedly hairy. Leaf solitary, erect, 100-160 x 1-3 mm, narrowly linear

, dark green to red-green; hairs sparse comprising mixtures of eglandular and glandular hairs upto 1 mm long. Scape 100-300 mm long, slender, somewhat wiry though brittle, reddish-green, covered with short hairs similar to those of leaf. Sterile bracts closely sheathing, 9-12 x 2-3 mm, narrowly obovate, subacute, abaxially hirsute. Floral bracts closely sheathing, 5-7 x 3 mm, oblong-elliptic to elliptic, abaxially hirsute. Flowers 1(-2), 20 mm diameter, dark green to dark reddish-green, usually marked with maroon or dark magenta, externally darker from numerous sessile ovoid glands; dorsal sepal strongly incurved over the column; lateral sepals spreading and erect (divergent); petals widely spreeading, suberect, distally incurved. Dorsal sepal 7-10 x 2-3 mm, narrowly obovate, cucullate (hooded); apex apiculate. Lateral sepals 7-11 x 2-3 mm, asymmetrically lanceolate, falcate, acute to subobtuse. Petals 7-10 x 1.5-2 mm, narrowly oblanceolate, asymmetrical, falcate, acuminate. Labellum articulated on short claw, whitish with few, broad purple transverse bars; callii dark purplish-black, lamina 5-6 x 4-4.5 mm, ovate in outline when flattened, erect in proximal half the curved forwards, apex recurved, 3-lobed; lateral lobes 1.5 mm wide, erect, embracing column, entire; mid-lobe 2 mm long, recurved with 4-8 pairs of dark purplish-black linear, papillate marginal calli 0.3 mm long, irregular of shape, decrescent to the apex. Lamina calli in 2 irregular rows, extending well onto the mid-lobe; stalks whitish; heads dark purplish-black, papillate. Basal calli 2, 0.5 mm, subsessile to sessile; head more or less oboid, curved. Longest cali 0.6 mm long; head 0.5 mm across, globose, papillate; stalk 0.3 mm long, slender. Distal calli subsessile to sessile, of irregular shape and arrangement. Column 5-6 x 2-2.5 mm, erect, incurved toward apex, greenish, spotted and blotched red, narrowly winged; central ridge 0.8 mm wide. Capsule 18-24 x 5-6 mm, green stripe with red, narrowly obovoid, very hairy.

Similar Taxa

A well marked species easily separated from the other New Zealand Caladenia by its tendency to grow as single often widely scattered plants; by its very tall, slender growth form; dark reddish-green, selfing flowers up to 20 mm diameter; labellum

decorated with sparse, rather broad, dark purple bands; broad labellum lateral lobes which incurve abruptly at the apex; 5-6 pairs of narrow marginal calli up to 0.6 mm long on the mid-lobe; and by the large dark-purplish black laminal callii arranged in two irregular rows which tend to become more closely spaced toward the mid-lobe apex.

Flowering

August - December

Flower Colours

Green,Red / Pink

Fruiting

October - February

Propagation Technique

Difficult - should not be removed from the wild.

Threats

Caladenia atradenia is a rather sparsely distributed and naturally uncommon orchid. However, it is quite likely that the apparent rarity of this species is also in part due to its being overlooked for despite its colourful flowers it is not easily seen amongst the leaf litter in which it usually grows. Nevertheless some populations have been lost due to weed invasions and land development.

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Not commercially available.

TAXONOMIC NOTES

Jones et al. (2001) erected the genus

Stegostyla for what they regarded as a distinct clade of South-eastern Australian, Tasmanian and New Zealand orchids that had usually been referred to as Caladenia. Subsequently Hopper et al. (2004) showed how the reorganisation of Caladenia by Jones et al. (2001) was unworkable and they recommended a return to Caladenia and the other allied Australian genera that had been recognised previously. Following discussion with S. Hopper and P. Weston (pers. comm., 2011, 2014) the treatment of Hopper et al. (2004) is preferred to that of Jones et al. (2001) and so is followed here.

Attribution

Fact Sheet prepared by P.J. de Lange (12 February 2007). Description based on Jones et al. (1997) - .

References and further reading

Hopper, S.D.; Brown, A.P. 2004: Robert Brown's Caladenia revisited, including a revision of its sister genera Cyanicula, Ericksonella and Pheladenia (Caladeniinae: Orchidaceae). Australian Systematic Botany 17: 1-240.

Jones, D.L.; Molloy, B.P.J.; Clements, M.A. 1997: Three new species and a new combination in Caladenia R.Br. (Orchidaceae) from New Zealand. The Orchadian 12: 221-229.

Jones, D.L.; Clements, M.A.; Sharma, I.K.; Mackenzie, A.M. 2001: A New Classification of Caladenia R.Br. (Orchidaceae). The Orchadian 13: 389-419.

 

This page last updated on 3 Dec 2014