Olearia telmatica
Common name
shell akeake, swamp akeake
Synonyms
None. First described in December 2008
Family
Asteraceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Trees & Shrubs - Dicotyledons
Chromosome number
2n = 108
Current conservation status
The conservation 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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. 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. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RR, RF
Previous conservation statuses
2012 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RF
2009 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RF
2004 | Not Threatened
Brief description
Small tree with oval dark green leathery leaves that are whiteish underneath inhabiting damp sites on the Chatham Islands. Trunk often hollow. Leaves 15-70mm long by 6-35mm wide. Flowers yellowish, in small clusters, appearing late winter. Seeds fluffy.
Distribution
Endemic. Chatham Islands: Rekohu / Wharekauir (Chatham), Rangihaute / Rangiauria (Pitt) and Hokorereoro / Rangatira / South East Islands.
Habitat
A conspicuous component of Chatham Island swamp forest, a vegetation type that has developed in sites that are either prone to seasonal flooding or almost permanently flooded throughout the year. These habitats include the margins of lakes, ponds, and slowly flowing rivers and streams, around springs or in other sites with perched water tables.
Detailed description
Small tree 4–8 m tall; main trunks up to 400 mm diameter. Bark light grey, shallowly fissured and smoothly textured on trunk and old branches; branchlets 1.6–2.1 mm diameter. Leaves 14–70 × 6–35 mm, elliptic, broadly elliptic, or obovate, upper surface green and glossy, lower surface with dense appressed tomentum, hairs fulvous or off-white, margin entire, apex acute to subacute, base cuneate to attenuate, petiole 4–7 mm long. Inflorescence an axillary panicle with 4–17 capitula, abscissing after fruiting; panicle primary branches in 2–4 opposite pairs, lowest pair of branches each with 1–3 capitula, upper branches each with 1 capitulum, capitula in opposite pairs; covered in fulvous or off-white hairs. Capitulum 5.0–7.2 mm long, involucre cylindric; involucral bracts 10–14, in 1–2 series, upper surface glabrous, lower surface sparsely to moderately covered with fulvous hairs. Florets 7–11 per capitulum; corolla usually lemon-yellow, sometimes cream to pale yellow. Achenes 1.4–1.7 × 0.6–0.7 mm, narrowly cylindric, light brown, with 4–5 pale ribs, sparsely to moderately hairy; pappus 2.8–4.2 mm long, finely scabrid.
Similar taxa
Olearia telmatica differs from the closely related akeake (O. traversiorum) by its restriction to permanently flooded swamp habitats, smaller stature, slender trunk, narrower leaves, lemon-yellow and less hairy corolla, less branched inflorescence with fewer capitula, fulvous hairs on the inflorescence, earlier flowering season, readily dispersed seed, and abscising inflorescences.
Flowering
August – October
Flower colours
Cream, Yellow
Fruiting
October – January
Propagation technique
Easily grown from fresh seed and semi-hardwood cuttings. Plants layer readily. Probably would flourish best in a permanently moist soil.
Threats
Shell akeake was formerly widespread across the two main islands, Rekohu (Chatham Island) and Rangiauria (Pitt Island). However most of its swamp forest habitat has now been cleared and there are very few places where this habitat survives intact. Most of the remaining swamp forest remnants on the islands are unfenced and stock have frequent access, and peripheral damage caused by wind throw, and the drying out of the peat soils are serious threats both to the species and this vegetation type. Another serious threat is recruitment failure. While seedlings are frequently seen in the more intact, and wetter swamp forest remnants, it seems that very few of these reach maturity.
Etymology
olearia: Named after Johann Gottfried Olearius, a 17th-century German scholar, writer of hymns and author of Specimen Florae Hallensis
Attribution
Fact sheet by Peter J. de Lange (14 December 2008). Description based on Heenan et al. (2008).
References and further reading
Heenan, P.B., P.J. de Lange, Houliston, G.J., Barnaud, A., and Murray, B.G. 2008: Olearia telmatica (Asteraceae: Astereae), a new tree species endemic to the Chatham Islands. New Zealand Journal of Botany 46(4): 567-583.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Olearia telmatica Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/olearia-telmatica/ (Date website was queried)