Coprosma chathamica
Common name
Chatham Island karamū, karamū
Synonyms
None (first described in 1902)
Family
Rubiaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Trees & Shrubs - Dicotyledons
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.
COPCHA
Chromosome number
2n = 132
Current conservation status
The threat classification status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley. Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – a suggested threat classification status has not been assessed by the NZTCS panel.
Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | At Risk – Naturally Uncommon | Qualifiers: IE, RR
Previous conservation statuses
2012 | At Risk – Naturally Uncommon | Qualifiers: IE, RR
2009 | At Risk – Naturally Uncommon | Qualifiers: IE
2004 | Range Restricted
Brief description
Canopy tree with pairs of oval leaves inhabiting scattered sites on the Chatham Islands. Twigs and leaf bases bearing small hairs. Leaves with pale veins which have a small pit at some of their junctions, those of juvenile plants to 12cm long, those of adults only 3-4cm long. Ripe fruit yellow.
Distribution
Endemic. Chatham Islands group: Rekohu (Chatham Island), Rangiauria (Pitt Island) and Rangatira (South-east Island)
Habitat
Coastal and inland forest. Mostly on peat and usually in sites that are at least temporarily waterlogged but also on limestone, schist and basalt outcrops in free draining situations. An important canopy tree which co-associates with matipo (Myrsine chathamica) on free draining soils, and swamp akeake (Olearia telmatica) in the waterlogged soils in the lowlands to form one of the main forest types. It is also prominent with tarahinau (Dracophyllum arboreum) in the southern tablelands forests, and less frequently with akeake (Olearia traversiorum) in dune forest and overlying basalt or schist.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FAC: Facultative
Commonly occurs as either a hydrophyte or non-hydrophyte (non-wetlands).
Features
Tree up to 15 m tall; trunk up to c.600 mm diameter; branches and branchlets rather stout, densely pubescent when young. Leaves on short 8-10 mm long fleshy-coriaceous petioles. Stipules triangular, pubescent, densely ciliate; apical denticle prominent black, surrounded on either side by 2-4 smaller denticles. Lamina of juvenile leaves subcoriaceous, 45-75 × 20-45 mm, dark green to green, broadly ovate to ovate-oblong, obtuse, mucronulate, base cuneately narrowed, margins often hairy; adult lamina 20-35 × 15-30 mm, dark green and rather glossy above, paler below, ovate to ovate-oblong, elliptic to oblong-elliptic, obtuse, mucronulate, base cuneately narrowed, margins slightly recurved, entire to distinctly undulose. Reticulated veins not or scarce evident above, evident below. Male flowers solitary or in clusters of up to 6 on shortly branched axillary peduncles; calyx 0 or vestigial; corolla funnelform, lobes 5, acuminate, > tube. Female flowers 1-6 together; calyx-teeth short, ciliolate; corolla tubular, lobes ovate, acute, > tube. Drupe yellow-red to orange, obovoid, slightly compressed to subdidymous, c.9-12 × 9-14 mm.
Manaaki Whenua Online Interactive Key
Similar taxa
A very distinctive species which on the Chatham Islands is not likely to be confused with any of the other Coprosma species present. The tree growth habit marks it well in the field, while the very large juvenile leaves with their usually distinctly hairy margins and smaller glossy, dark green adult leaves which usually have distinctly undulose margins readily distinguish it. Allan (1961) followed W.R.B. Oliver and placed it as close to C. petiolata (Kermadec islands) and C. repens in Sectionion Petiolatae. Morphologically it has little to do with these two species, sharing more features in common (especially the growth habit, adult leag shape, fruits and pyrene morphology) with the arborescent Norfolk Island endemic C. pilosa. However, molecular data clearly shows that C. chathamica is closely allied to C. repens.
Flowering
August - December
Flower colours
Green
Fruiting
November - May
Life cycle
Fleshy drupes are dispersed by frugivory (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed and semi-hardwood cuttings. An attractive species that given time will grow in to a large tree so it needs plenty of space. Does best planted in a permanently moist soil (it can tolerate periodic water logging).
Threats
An Island endemic that is not really threatened. One of the major forest trees on the Chatham Islands.
Etymology
coprosma: From the Greek kopros ‘dung’ and osme ‘smell’, referring to the foul smell of the species, literally ‘dung smell’
chathamica: From the Chatham Islands
Attribution
Description based on Allan (1961) and supplemented with additional measurements and observations taken from herbarium specimens and wild plants.
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I, Government Printer, Wellington.
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
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Coprosma chathamica Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/coprosma-chathamica/ (Date website was queried)