Classification
 Nomenclature
Scientific Name:
Olearia semidentata Decne., Voy. Venus, Bot. [Atl.] t. 13 (1846)
Synonymy:
Holotype: Ile Chatam [Chatham Islands], 9bre [i.e, November] 1838, M. Pfihl s.n. (holotype: P 711315
Vernacular Name(s):
Chatham Island aster; Hangatare; Makora; Purple tree daisy
 Description

Shrub up to 1 m. tall; branchlets slender, clad in white floccose tomentum. Lvs 3·5–7 cm. × 6–9 mm., narrow-lanceolate, subsessile, rather distantly serrate in upper half, glab. above when mature, clad in white appressed tomentum below. Peduncles slender, tomentose, 5–8 cm. long, with ∞ lanceolate bracts. Capitula 2.5–3·5 cm. diam.; phyll. pilose towards tips and on margins, acute, up to 1 cm. long; ray-florets purple, disk-florets violet-purple; achenes linear, pubescent, c. 3 mm. long; pappus-hairs up to 7 mm. long.

[From:  Allan (1961) Flora of New Zealand. Volume 1.]

 Biostatus
Indigenous (Endemic)
 Phenology

Flowering: Nov.–Dec.

 Bibliography
de Lange, P.J.; Norton, D.A.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Hitchmough, R.; Townsend, A.J. 2009: Threatened and uncommon plants of New Zealand (2008 revision). New Zealand Journal of Botany 47: 61–96. [Naturally uncommon]
de Lange, P.J.; Norton, D.A.; Heenan, P.B.; Courtney, S.P.; Molloy, B.P.J.; Ogle, C.C.; Rance, B.D. 2004: Threatened and uncommon plants of New Zealand. New Zealand Journal of Botany 42(1): 45–76.
de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series. No. 22. [Naturally Uncommon]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Naturally Uncommon]
Decaisne, J. 1846: Voyage Autour du Monde sur la Frégate la Venus Pendant les Années 1836-1839 [par A.A. Du Petit-Thouars]: Atlas (Botanique). Gide & Cie, Paris.
Nelson, E.C. 1988: Holotype of Olearia semidentata Decne. New Zealand Journal of Botany 26: 464–466.
Saldivia, P.; Wagstaff, S.J.; Breitwieser, I.; Orlovich, D.A.; Lord, J.M. 2022: A generic taxonomic synopsis of the Pleurophyllum clade (Asteraceae: Astereae: Celmisiinae) with the recognition of the New Zealand endemic new genus Macrolearia. Systematic Botany 47(2): 607–634.