Species

Muehlenbeckia astonii

Etymology

Muehlenbeckia: Named after a botanist named Muehlenbeck
astonii: after Aston

Common Name(s)

Shrubby tororaro, wiggywig, mingimingi

Current Conservation Status

2012 - 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

2009 - Threatened - Nationally Endangered
2004 - Threatened - Nationally Vulnerable

Qualifiers

2012 - CD, RF
2009 - CD, RF

Authority

Muehlenbeckia astonii Petrie

Family

Polygonaceae

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.

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Trees & Shrubs

Synonyms

None

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.

Chromosome No.

2n = 20

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Commonly available from most commercial plant and specialist native plant nurseries. Can be purchased from Oratia Native Plant Nurseries (info@oratianatives.co.nz).

Attribution

Fact sheet prepared for NZPCN by P.J. de Lange December 2004. Original description by P.J. de Lange.

This page last updated on 13 Mar 2014