Species
Dichelachne lautumia Edgar & Connor
Etymology
Dichelachne: two-pronged and woolly
Current Conservation Status
2018 - Threatened - Nationally Endangered
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
2012 - Threatened - Nationally Critical
2009 - Threatened - Nationally Critical
2004 - Range Restricted
Qualifiers
2012 - RR, St
2009 - St, RR
Authority
Dichelachne lautumia Edgar et Connor
Family
Poaceae
Flora Category
Vascular - Native
DICLAU
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
Grasses
Synonyms
Deyeuxia
Distribution
Endemic. South Island, Marlborough, mainly found near the mouth of the Flaxbourne River. Also recorded slightly further south from the lower Waima (Ure) River.
Habitat
One population is found mainly on limestone talus, both soil and rocky debris derived from quarrying activities, with a few plants in crevices and on ledges on natural rock faces. The second population is on limestone derived alluvial terraces. All plants are in full light with very little shelter
Features
Robust grey-green to orange-green tufts 450-650 mm tall. Branching extravaginal. Leaf-sheath chartaceous with membranous margins, more or less distinctly ribbed, glabrous, straw-coloured, or reddish purple, especially in culm leaves. Ligule 0.7-1.0 mm long, truncate, erose, sparsely ciliate, undersides scabrid. Leaf-blade 60-200 x 15-30 mm, greyish green maturing orange-green or reddish, undersides smooth, upper surface strongly ribbed, prickle-toothed on ribs; margins finely prickle-toothed. Culm 300-450 mm long, nodes green to purple with an upper fringe of dense, appressed hairs, internodes glabrous. Panicle 100-160 x 10-15 mm, linear-lanceolae, dense, contracted above, longer lower branches in slightly more distant clusters, scarcely spreading, spikelet bearing to base; rachis, branches and pedicels with short hair-like prickle-teeth. Spikelets 6-8 mm, green to straw-coloured or suffused with purple. Glumes 1-nerved, equal or upper very slightly longer, c.6mm, submembranous, elliptic-lanceolate, acuminate, keels finely prickle-toothed. Lemma less than or equal to glumes, 6-7 mm, subcoriaceous, papillose, minutely prickle-toothed above, apex bifid with hyaline finely acuminate lobes 0.5-1.0 mm long; awn 8-12 mm, mid-dorsal, or arising from slightly above midway, geniculate, twisted, very hairy below. Palea less than lemma, folded, keels prickle-toothed above, apex ciliate. Callus c.0.2 mm long, hairs up to 4 mm long. Rachilla 0.2-0.7 mm, glabrous or with a few hairs; prolongation 0.5 mm long. Lodicules 0.5 mm, cuneate, ciliate. Stamens 3; anthers 1.0-1.5 mm long. Ovary 1.0-1.3 mm; stigma-styles 0.7-1.5 mm long, hairs almost to base. Seed 3.5 x 1.0 mm, beaked.
Similar Taxa
Distinguished from the allied D. crinita(L.f.) Hook.f. by the callus hairs with are equal to or greater than 3 mm (in D. crinita they are less than 1 mm); by the shorter awn (8-12 cf. 20-30 mm in D. crinita) and by the twisted rather than straight column.
Flowering
November - January
Fruiting
December - May
Propagation Technique
Difficult to grow. Needs very well drained soil (it does best with the addition of limestone chips), in a sunny location. Dislikes humidity and damp ground. Fresh seed germinates easily.
Threats
Known from a only a few populations. Currently these seem to be secure and stable although the species remains very uncommon.
Chromosome No.
2n = 70
Endemic Taxon
Yes
Endemic Genus
No
Endemic Family
No
Life Cycle and Dispersal
Florets are wind dispersed (Thorsen et al., 2009).
Attribution
Description modified from Edgar and Connor (2000)
References and further reading
Edgar, E.; Connor, H.E. 2000: Flora of New Zealand. Vol. V. Grasses. Christchurch, Manaaki Whenua Press. 650 pp.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309
This page last updated on 24 Jul 2014