Flora of New Zealand Series

Rhizomatous perennial; stems mat-forming, c. 1.2 mm diam., < 10 cm long, soon rooting and covered by soil; erect branchlets < 2 cm long. Lvs 1.5-9 cm long; stipules entire; leaflets 11-13, broad-obovate, 3-10 × 2.5-8 mm, with 7-14 obtuse teeth, dull grey-green or pale milky green on both surfaces, with veins and margins of lower surface hairy. Capitulum ± sessile, c. 5 mm diam. at flowering, c. 1 cm diam. at fruiting; florets c. 10; sepals 4; stamens 2; anthers white; styles 2, white; achenes 2. Fr. turbinate, c. 3 × 3 mm, sparsely to densely hairy; spines 4, yellow or crimson, < 1.5 cm long, bearing many retrorse, soft hairs at the tip.

S.: common in catchments of Waitaki and Clutha Rivers, also collected from Molesworth (Marlborough), Amberley Beach, Kaitorete Spit and Ashburton Lakes (Canterbury).

Endemic.

Drier montane grassland.

FL Nov-Dec FT Dec-Apr.

A. buchananii is variable in foliage colour, development of spines, and spine colour, with coexisting forms. Var. inermis Bitter, lacking spines on the fr., and var. picta Allan, with foliage pale olive-green and spines crimson, accepted by Allan (1961), are part of this complex. A. depressa Kirk is a synonym of A. buchananii var. picta.

An entity similar to A. buchananii but with glaucous lvs thinner in texture is restricted to subalpine herbfield of C. Otago ranges, and deserves taxonomic recognition.