The New Zealand Plant Conservation Network

Species

Atriplex hollowayi

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

Common Name(s)

Holloway's crystalwort

Current Conservation Status

2012 - Threatened - Nationally Critical

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 Vulnerable
2004 - Threatened - Nationally Critical

Qualifiers

2012 - CD, EF, OL
2009 - CD, EF, Inc, OL

Authority

Atriplex hollowayi de Lange et D.A.Norton

Family

Amaranthaceae

Flora Category

Vascular - Native

NVS Species Code

ATRHOL

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

None

Distribution

Endemic. North Island, formerly recorded from Te Paki south and east to Hicks Bay, including Mayor (Tuhua) Island, with a disjunct southerly gathering made by Thomas Kirk in the 1800s from Lyall Bay, Wellington. Now known naturally only from Waikuku and Whareana Beaches, on the eastern side of Te Paki.

Habitat

Sandy Beaches, at or just above the high water tide mark. Usually found at or in the vicinity of a fresh water stream draining across a beach

Features

Annual, succulent, densely branched herb, forming circular 0.8 x 1.2 m mounds on sandy beaches just above mean annual high water tide mark. All exposed parts copiously covered in fine, sugar-like, deciduous, spherical, glistening, ball-like papillae. Branches 10-50 mm long, succulent, creamy yellow, rooting at nodes. Stems pale yellow. Leaves 2-12 x 1-6 mm, grey-green, margins distinctly but irregularly toothed. Plants monoecious. Male flowers axillary, in clusters of 2-4, rarely single; perianth lobes 5, green or pale-cream, 0.8-1 mm, elliptic-oblong; stamens 5, anthers yellow; female flowers minute, 0.8-1.2 mm, shortly stipitate, solitary or paired in leaf-axils. Perianth absent, bracteolea fused for ½ length, lips triangular, obtuse, laciniate, fimbriate to entire; styles 2 not connate; stigmas 2, white, 0.7-1 mm. Fruits 2.8-4.0 x 1.5-2.3, straw-yellow, urceolate, papery. Seed circular, convexm 0.9-2 mm diam., chestnut-brown maturing purple-brown.

Similar Taxa

Atriplex billardierei (Moq.) Hook.f., which can be distinguished by its smooth margined leaves, fused, paired stigma, larger fruits and seeds. A. billardierei appears to have never grown in A. hollowayi habitats, and was historically known in New Zealand only from Southland, Stewart Island and Chatham Island sand beaches. Currently it is only known in New Zealand from the Chatham Islands, where it is seasonally abundant.

Flowering

October - February

Flower Colours

Cream,Green

Fruiting

December - April

Propagation Technique

Easily grown from seed that has first been soaked in fresh water. Can be grown from softwood cuttings early in growing season.

Threats

At risk from trampling and/or browsing by livestock and palatable to most herbivores. There is some historical evidence suggesting that some of this species decline was caused by botanists collecting whole plants - which to an annual species can be a serious threat. Holloways Crystalwort is also threatened by competition from other introduced strand plants, summer cyclonic storms, human beach users - especially from the ever increasing use of All Terrain Vehicles on sand beaches.

Chromosome No.

2n = 18

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 10 May 2014