Senecio repangae
Synonyms
Senecio repangae de Lange et B.G.Murray subsp. repangae
Family
Asteraceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledonous composites
Chromosome number
2n = 100
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.
2018 | Threatened – Nationally Vulnerable
Previous conservation statuses
2017 | Threatened – Nationally Vulnerable | Qualifiers: DP, PD, Sp
2012 | At Risk – Naturally Uncommon | Qualifiers: IE, Sp
2009 | At Risk – Naturally Uncommon | Qualifiers: EF
2004 | Sparse
Distribution
Endemic. North Eastern North Island, on offshore islands only, from Te Wakatehaua to Cuvier (Repanga) Island
Habitat
Strictly coastal. A species of mainly offshore islands where it grows in the immediate vicinity of seabird colonies (gulls, shags, petrels, diving petrels). Also an opportunist on islands colonising sites where trees have fallen, pasture, and even behaving as a minor weed within lighthouse settlements.
Features
Erect, sparingly branched annual to short-lived perennial herb 0.2-1.2 m tall, arising from a stout woody rootstock. Foliage dull dark grey-green. Leaves pilose hairy; basal leaves cuneately narrowed or shortly petiolate, broadly elliptic-oval or rhomboidal, coarsely toothed, rarely lyrate-pinnatifid. Mid cauline leaves amplexicaul, usually deeply bifid at base, narrow, ovate, elliptic, lanceolate or oblong, pinnately lobed 1-2-pinnatifid with segments lanceolate to oblong, entire or few-toothed, gradually diminishing in size up stem, becoming apetiolate. Uppermost leaves smaller, lanceolate, dentate or pinnatifid. Supplementary bracts 5-9, narrow, 2-5 mm long; lower most usually dentate; margins often slightly villous, apex villous. Capitulum subcylindric; involucral bracts 9-17, narrowly lanceolate, 8-14 mm long, glabrescent, with purple-black villous apices. Ray florets (0-)3-9, widely and irregularly spaced; ligules 1-2 mm, sulphur yellow; margin involute; apex recurved, incised 3-4 times. Disc yellow 4-5 mm diameter. Cypsela subcylindric, 2.5-3 mm long, grey, slightly narrowed at apex, covered in hairs, but hairs distinctly denser toward apices and between ribs.
Similar taxa
Senecio pokohinuensis is similar differing by its glabrescent, glaucous foliage, cylindrical involucrum, shorter involucral bracts, and ray florets (up to 14 c.f. 9 in S. repangae) which are not recurved, and are evenly spaced (de Lange et al. 2022). Senecio repangae had previously been included with S. lautus, from which it differs in its sparingly branched, erect growth form, non-succulent foliage, greater number of involucral bracts (9-20 cf 11-13), longer bracts (6-14 mm c.f. 4-7 mm), shorter ligules (1-4 mm cf 5-9 mm) and grey, subcylindric rather than black, narrowly cylindric cypsela. Senecio repangae has 2n = 100 chromosomes and S. lautus 2n = 40.
Flowering
September - March
Flower colours
Yellow
Fruiting
September - April
Propagation technique
Easy from fresh seed. Prefers full sun. Can become invasive. Despite its weedy nature it makes an excellent pot plant
Threats
Aside from Cuvier (Repanga) Island where it is abundant this subspecies is very uncommon and is known only from small, widely scattered populations. In some locations where this species was found in the late 1980s and early 1990s it has now declined.
Etymology
senecio: From the Latin senex ‘old man’ (probably referring to the bearded seeds)
repangae: Taken from ‘Repanga’ which is te reo Maori for Cuvier Island the type locality of the species.
Where To Buy
Not commercially available.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 1 November 2008. Description based on de Lange & Murray (1998) and de Lange et al. (2022).
References and further reading
de Lange, P.J.; Murray, B. G. 1998: Senecio repangae (Asteraceae): a new endemic species from the north-eastern North Island, New Zealand. New Zealand Journal of Botany 36(4): 509-519.
de Lange, P.J.; Pelser, P.B.; Liew, C-S.; Marshall, A.J. 2022: Senecio pokohinuensis (Asteraceae), a new combination for an endemic species of Mokohinau Islands, Hauraki Gulf (Tikapa Moana o Hauraki), northern Te Ika a Maui / North Island, Aotearoa / New Zealand. Ukrainian Botanical Journal 79(3): 125–129. https://doi.org/10.15407/ukrbotj79.125
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Senecio repangae Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/senecio-repangae/ (Date website was queried)