The New Zealand Plant Conservation Network

Species

Atriplex billardierei

Etymology

Atriplex: From an ancient Latin name whose derivation is uncertain, but a possible explanation is the name comes from the Greek a- 'without' and traphein 'nourishment' because many of these species grow in arid desert soils
billardierei: Named after Jacques Houttou de Labillardiere (1755-1834), 19th century French botanist who described several New Zealand plants

Common Name(s)

Crystalwort

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 - At Risk - Relict
2009 - At Risk - Relict
2004 - Range Restricted

Qualifiers

2012 - EF, TO
2009 - EF, TO

Authority

Atriplex billardierei (Moq.) Hook.f.

Family

Amaranthaceae

Flora Category

Vascular - Native

NVS Species Code

ATRBIL

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Theleophyton billardierei Moq., Atriplex chrystallina Hook.f.; Obione billardieri Moq.; Theleophyton chrystallina Hook. f.; Theleophyton billardierei Moq.; Obione billardierei Moq.

Distribution

Indigenous to New Zealand, Formerly present in the Foveaux Strait area and on Stewart Island, Last seen in that area in 1982. Present on the Chatham Islands. Also in Australia where it is apparently extinct except in Tasmania.

Habitat

It is generally found in the strand zone on open beaches and sandy banks through the build up of sand where it forms low sandy mounds.

Features

Decumbent, sprawling, lightly branched, succulent, leafy, monoecious, annual herb, forming circular mats or low mounds within sand, to 2 or 3 m diameter. Branches 20-150 mm long, succulent, cream or yellow, rooting at nodes; exposed surfaces coated with deciduous, watery, spherical, glistening papillae. Leaves 5-20 x 2-7 mm, oblong-obovate, ovate, elliptic, or lanceolate, green to glaucous-green, succulent. Petioles short, 0.5-1 mm. Leaf surface sparsely to densely covered in deciduous watery, spherical, glistening papillae; apex and base obtuse; margin entire, very rarely within one or two lobes. Male flowers axillary, in clusters of 3-4, rarely single; occasionally with rudimentary stigma; perianth lobes 5, green or pale cream, 1.2 mm long. Elliptic-oblong, apex inflexed, cucullate, margins laciniate-crenate, abaxial surface covered in watery papillae; stamens 5, filaments 0.6 mm long, white, anthers 0.2 mm long, oblong, basifixed, pollen sulphur yellow. Female flowers minute, 1-2 mm, shortly stipitate, borne in leaf axils, either solitary, or in pairs, usually accompanied by a short shoot with one pair of reduced leaves. Peduncles minute, 0.25 mm long. Perianth absent; bracteoles fused for ¾ quarter of their length, lips entire; external bracteole surfaces glistening, papillae 0.2-0.3 mm diameter; style connate, stigmas 2.1-1.3 mm, white, half exserted, tapering-terete, 0.1-0.2 mm diameter, exserted portion with antrorse papillae, Ovary flattened at right angles to lips, 0.5 mm diameter, sessile or almost so. Fruiting bracteoles 3.3-9.5 x 2.2-6.0 mm, light brown or tan, subsessile or shortly stipitate; urceolate, valves rigidly fused for ¾ of their length, swollen toward base, corky, otherwise coriaceous with an entire margin, apex usually entire, rarely finely crenate, or fimbriate; surface densely coated in watery papillae 0.2-0.3 mm diameter. Seed circular in outline, convex, 1.8-4.0 mm diameter, testa chesnut-brown, maturing purple-brown, fading to black in dried specimens, surface matt, ± smooth. or finely rugose; radicle lateral, erect.

Similar Taxa

Atriplex prostrata DC. often grows in similar habitats but has large arrowhead shaped leaves. A. buchananii (Kirk) Cheeseman has been confused with A. billardierei but it lacks the distinctive spherical pustules on the leaves; also it has smaller fruit. Cakile edentula (Bigelow) Hook. and Cakile maritima Scop. are introduced plants that occupy similar habitats.

Flowering

November to February

Flower Colours

Cream,Green

Fruiting

December to April

Propagation Technique

Easy from fresh seed but difficult to maintain

Threats

Possibly very vulnerable to human disturbance. Wide-scale coastal erosion and storm inundation are probably the greatest natural threats. It is occasionally browsed by sheep and cattle and horses. There is evidence from Australia and New Zealand that it is susceptible to competition from other introduced strand plants. Plants are easily killed by trampling and by vehicles using beaches. In much of its former range it has also suffered from collection of specimens for museums.

Chromosome No.

2n = 18

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Spongy nutlet dispersed by water and possibly also wind and granivory (Thorsen et al., 2009).

This page last updated on 10 May 2014