Acrothamnus colensoi
Biostatus
Native – Endemic taxon
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Simplified description
Low-growing sprawling much-branched to weakly branched shrub (branches often subscandent). Leaves spreading, small bronze-green, pinkish green, glaucescent to dark red-brown with pale yellow margins, striped white beneath. Leaf margins finely hairy otherwise leaves glabrous. Flowers in small subterminal to terminal racemes, white. Fruit globose, glossy, white, pink, red crimson to almost black, fleshy.
Flower colours
White, Yellow
Detailed description
Dioecious (?gynodioecious) sprawling, prostrate, glaucescent pinkish green to red-brown shrubs forming much-branched to unevenly, sparingly-branched almost lianoid patches, 0.2-0.5 × 1.0-2.0 m. Branches spreading, ascending to erect, weakly ribbed to ± terete, grey-brown, unevenly pubescent but becoming glabrous with age. Leaves alternate, spreading, glabrous, bronze-green, pinkish green, glaucescent to dark red-brown with pale yellow margins, abaxially distinctly 3-5-nerved but veins not or scarcely raised above surface, veins greenish, interveinal grooves white; lamina 5-10 × 1-4 mm, narrow-oblong, oblong, concavo-convex; margins distinctly thickened, ± recurved, initially finely ciliolate, soon glabrous; apex obtuse, apiculate to mucronulate. Inflorescences near ends of branches, terminal, and/or in upper axils; racemose, 2-5-flowered, terminating in a bud-like rudiment. Flowers subtended by a bract and 2 keeled bracteoles; bract pinkish green to red, up to 2.5 mm long, glaucescent, broadly ovate, obtuse, ciliolate; bracteoles similar but smaller and distinctly keeled. Sepals up to 4 mm long, elliptic-oblong to ovate, obtuse, ciliolate, similar but smaller, imbricate with stomata only on the adaxial surface. Flowers seemingly unisexual, 6-8 mm long; corolla tube 4-5 mm long, hairy toward lobes; corolla-lobes 2.8-3.3 mm long, both surfaces copiously covered in hairs in distal half. Anthers emarginate, 0.4-0.6 mm long, apically attached by a short thin filament inserted near base of corolla tube sinus; the filaments ± exserted to almost hidden within tube, 0.3-0.5 mm long. Ovary 4-5-locular, spheriodal, glabrous, 0.5-1.0 × 0.5-0.8 mm wide; style straight, glabrous, 0.8-1.8 mm long; stigma 0.1 mm long usually immersed in tube, rarely partially exserted. Fruit, white, pink, red, dark crimson (rarely almost black), 4-5 mm diameter, globose. Endocarp 2.5-3.5 × 2.2-3.0 mm, pale brown, brown to orange-brown, broadly obovate, broadly ellipsoid to ovoid, indistinctly, longitudinally ridged 5×, surface somewhat granular.
Similar taxa
Very superficially similar to Montitega, which differs by having narrow-oblong to narrow-elliptic; adaxially glaucous to dark brown-green, abaxially white, leaves whose margins are slightly thickened towards the base, and whose flowers are solitary rather than in racemes.
Distribution
Endemic. New Zealand: North and South Islands from about Kaingaroa Plain south.
Habitat
Montane to alpine extending to lower elevations in shrubland, tussock grassland and peat bogs in the southern part of its range
Detailed taxonomy
Genus
Family
Synonyms
Leucopogon colensoi Hook.f., Leucopogon suaveolens Hook.f., Cyathodes colensoi (Hook.f.) Hook.f.
Taxonomic notes
This species has also been treated as Acrothamnus suaveolens (Hook.f.) C.J. Quinn (also known as Leucopogon suaveolens Hook.f.). However, recent DNA based research backed up with sound morphological characters has recognised that A. colensoi is distinct from A. suaveolens, which is endemic to Borneo (Quinn et al. 2005). Acrothamnus colensoi also has a very distinctive chromosome number quite unlike that seen in other New Zealand members of the ericoid Styphelieae (Murray & de Lange 2013).
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
September - February
Fruiting
November - June
Life cycle and dispersal
Fleshy berries by bird, reptile and invertebrate herbivory (Thorsen et al. 2009).
Propagation technique
Difficult. Should not be removed from the wild.
Other information
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for October 2020 for the full story.
Etymology
colensoi: Named after William Colenso (7 November 1811 - 10 February 1899) who was a Cornish Christian missionary to New Zealand, and also a printer, botanist, explorer and politician.
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
ACRCOL
Chromosome number
2n = 146
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Otago: 2025 | Regionally Not Threatened
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
Referencing and citations
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I. Wellington, Government Printer.
Murray, B.G.; de Lange, P.J. 2013: Contributions to a chromosome atlas of the New Zealand flora – 40. Miscellaneous counts for 36 families. New Zealand Journal of Botany 51: 31–60.
Quinn, C. J.; Brown, E. A.; Heslewood, M. M.; Crayn, D. M. 2005: Generic concepts in Styphelieae (Ericaceae): the Cyathodes group. Australian Systematic Botany 18: 439-454.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309.
Webb, C.J.; Simpson, M.J.A. 2001: Seeds of New Zealand Gymnosperms and Dicotyledons. Christchurch, Manuka Press.
Attribution
Fact Sheet prepared for the NZPCN by P.J. de Lange (19 November 2014). Description based on Allan (1961), Quinn et al (2005), Webb & Simpson (2001) and observations made from fresh and dried specimens
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Acrothamnus colensoi Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/acrothamnus-colensoi/ (Date website was queried)