Muehlenbeckia astonii
Common name
shrubby tororaro, wiggywig, mingimingi
Synonyms
None
Family
Polygonaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Trees & Shrubs - Dicotyledons
Chromosome number
2n = 20
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 | Threatened – Nationally Endangered | Qualifiers: CD, RF
Previous conservation statuses
2009 | Threatened – Nationally Endangered | Qualifiers: CD, RF
2004 | Threatened – Nationally Vulnerable
Brief description
Rare brownish shrub with tangled zig-zagging branches bearing small heart shaped leaves and white fruit with a black seed on top. Twigs orange. Leaves 2-15mm wide, with large dent at tip, on a 3-10mm long often brown grooved stalk, in clusters. Flowers small.
Distribution
Endemic. North and South Islands. In the North Island known from Honeycomb Light (Eastern Wairarapa) south to Cape Palliser and just west of Sinclair Head. In the South Island in Marlborough formerly present on the Wairau Bar and Wither Hills, now known only from Clifford Bay, the lower Awatere Catchment to Cape Campbell and Kekerengu. Also in North Canterbury, on Banks Peninsula near Lake Forsyth and on Kaitorete Spit. An old herbarium specimen in Kew suggests it may have once been in the lower Waitaki Valley, South Canterbury.
Habitat
Coastal to lowland. This species is associated with “grey” scrub communities, largely confined to drier lowland parts of eastern New Zealand. It is found on moderate to high fertility soils. The plant is often found in association with Coprosma crassifolia Colenso, Coprosma propinqua A,Cunn., Muehlenbeckia complexa (A.Cunn.) Messn. (small-leaved pohuehue), Discaria toumatou Raoul (matagouri), Olearia solandri Hook.f. (coastal tree daisy), Ozothamnus leptophyllus (G.Forst.) I.Breitwieser et J.M.Ward (tauhinu) and Rubus squarrosus Fritsch (leafless lawyer).
Features
Deciduous, gynodioecious shrub forming dense, interwoven masses up to 4 x 4 m. Stems 10-20 mm diam., maroon-black, cane-like, numerous, arising from a stout, woody, rootstock, 0.5-1 m diam. Branches numerous. Branchlets slender, flexuous, divaricating and interlacing. Leaves in fascicles of 2-5 on short branchlets, or widely spaced along elongated emergent branchlets; petiole slender 3-10 mm; leaf lamina 2-15 mm diam., broadly-obcordate, rarely pandurate or entire; apex usually notched 1(-4) times, cuneately narrow to base. Flowers green or white, on short, axillary fascicles. Male and perfect flowers present on the same plant, the male flower bearing 8 functional stamens, and a rudimentary gynoecium; perfect flowers with functional stamens and gynoecium; female flowers on separate plants, ovary bluntly trigonous; stigmas 3, fimbriate, androecium rudimentary. Fruit an exposed 2-2.5 x 1.25 mm trigonous, dull black rugose nut; surrounding tepals white, succulent.
Similar taxa
Muehlenbeckia complexa is somewhat similar but this is a scrambler, not a shrub and has twining, tangled, tomentose, orange-brown young stems with no distinct trunk nor thickened branches. The nuts of M. complexa fruits has shiny faces, while those of M. astonii are distinctly rugose
Flowering
August - January (- May).
Flower colours
Green, White
Fruiting
October - June.
Propagation technique
Easy from fresh seed and hardwood cuttings, which should be taken in winter. An excellent shrub for hedges and wind breaks. Once established very drought tolerant. The deciduous habit is unusual, and the bare, interlacing, wiry dark stems in winter are as attractive as the bright green foliage seen in summer. The fleshy white fruits are sugary, edible, and attract birds and lizards to the garden. Will hybridise with other Muehlenbeckia species, so if pure seed is needed grow well away from other species. Most horticultral stock is female and so will not set viable seed. Male plants have varying frequencies of perfect flowers, and so can set viable seed.
Threats
The survival in the wild of Muehlenbeckia astonii is threatened by lack of regeneration due to competition from exotic grasses, browsing animals and trampling. It is also threatened by loss of its original habitat through disturbance, fragmentation and fire. Many of the shrubby tororaro that survive in the wild are single plants isolated from others of their species. Because male and female flowers occur on separate plants, these specimens have no opportunities to reproduce.
Etymology
muehlenbeckia: Named after a botanist named Muehlenbeck
astonii: After Aston
Where To Buy
Commonly available from most commercial plant and specialist native plant nurseries.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange December 2004. Original description by P.J. de Lange.
References and further reading
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Muehlenbeckia astonii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/muehlenbeckia-astonii/ (Date website was queried)