Shawia telmatica
Common names
shell akeake, swamp akeake
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 | At Risk – Declining | Qualifiers: CI, DPR, DPS, DPT, IE, PF, RR, RF
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Simplified 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.
Flower colours
Cream, Yellow
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
Shawia telmatica differs from the closely related akeake (S. 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.
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.
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.
Detailed taxonomy
Genus
Family
Synonyms
Olearia telmatica Heenan & de Lange
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
August – October
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.
Other information
Etymology
shawia: After Thomas Shaw (1694-1751), English scholar and traveller.
Chromosome number
2n = 108
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 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RR, RF
2012 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RF
2009 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, IE, RF
2004 | Not Threatened
Referencing and citations
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.
Saldivia, P.; Nicol, D.A. 2025: Reinstatement, broader circumscription, and infrageneric classification of Shawia (Astereae, Celmisiinae), a large woody genus endemic to Australasia. Phytoneuron 49: 1–43.
Attribution
Fact sheet by Peter J. de Lange (14 December 2008). Description based on Heenan et al. (2008).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Shawia telmatica Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/shawia-telmatica/ (Date website was queried)