Heenan, P.B.; de Lange, P.J. 2004: Alternanthera denticulata (Amaranthaceae) in New Zealand: a new addition to the indigenous or naturalised flora? New Zealand Journal of Botany 42: 739–745.
Details
Heenan, P.B.; de Lange, P.J. 2004: Alternanthera denticulata (Amaranthaceae) in New Zealand: a new addition to the indigenous or naturalised flora? New Zealand Journal of Botany 42: 739–745.
Article
Taxonomic concepts
Descriptions
Perennial herbs with a slender tap root; stems prostrate to erect, 2.0–3.5 mm diam., green and flushed pink, glabrous to sparsely hairy, with two decurrent lines of hairs, nodes tomentose. Leaves (20–)30–83 × 6–12 mm, leaves usually narrowly elliptic or lanceolate, sometimes linear to linear- oblong, light green or yellow-green with midrib and lateral veins pink, glabrate to sparsely hairy on margins, midrib, and both surfaces, apex acute; margins distinctly denticulate; base attenuate. Spikes globular or shortly oblong, 0.5–0.8 mm diam., clustered, with 15–20 flowers; rachis sparsely hairy, flowers subtended by 1 bract and 2 bracteoles; bracts and bracteoles 1.5–2.0 × 0.6–0.8 mm, lanceolate, cream, glabrous, membranous, shortly acuminate to acute. Perianth segments 2.3–2.4 × 0.6–0.8 mm, lanceolate, cream, glabrous, membranous, shortly acuminate to acute; anthers c. 0.15 mm long, yellow; filaments 3–4 mm long, translucent; style 0.1– 0.2 mm long; stigma capitate; ovary 0.4–0.5 mm long, green. Fruit 1.7–1.8 × 1.9–2.1 mm, cream and fl ushed pink, obovoid, compressed, indehiscent. Seeds 0.9–1.0 × 0.8–0.9 mm, cream to yellow, often with a light brown centre, compressed.
Identification keys
Key to Alternanthera in New Zealand
1
Inflorescences pedunculate, peduncles often > leaves, axillary or terminal
Inflorescences sessile, axillary
2
Leaves broadly elliptic or obovate, mostly > 1 cm wide; inner and outer tepals unequal, longer tepals spine-tipped; inflorescence obovoid-oblong
Leaves narrowly elliptic, oblong, or linear-oblong, < 1.2 cm wide; inner and outer tepals ± equal, not spine-tipped; inflorescence ± globular
3
Stems prostrate to erect; leaves usually narrowly elliptic or lanceolate, sometimes linear to linear-oblong, mostly > 30 mm long and > 6 mm wide, light green or yellow-green, margins distinctly denticulate
Stems prostrate; leaves linear-oblong, mostly < 30 mm long and < 5 mm wide, dark green, margins entire or obscurely denticulate
Reproduced with permission from New Zealand Journal of Botany and The Royal Society of New Zealand Te Apārangi.
Cited scientific names
Metadata
c234a258-0c23-4c55-8b5b-e8781a8100fe
reference
Names_Plants
12 July 2005
5 December 2012