Epilobium astonii
Common name
Aston’s willowherb
Synonyms
Epilobium pubens var. astonii Allan
Family
Onagraceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledons other than Composites
Chromosome number
2n = 36
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: DP, RR
Previous conservation statuses
2012 | At Risk – Naturally Uncommon | Qualifiers: RR
2009 | At Risk – Naturally Uncommon
2004 | Range Restricted
Brief description
A fairly large hairy Epilobium similar to E. pubens but larger in most features, and highly branched, prefering dryer montane to alpine rocky areas in the eastern central part of the North Island axial ranges.
Distribution
Endemic. North Island on the main axial ranges from the high points of the Raukumara Range south to the Raukumara and northern Ruahine Ranges.
Habitat
A subalpine to alpine species (760-1370 m a.s.l.) favouring greywacke (mainly the arenite facies) but also known from limestone. Usually found on cliff faces, often along canyon and gorge walls, sometimes on exposed boulders along ridge lines.
Features
Heavily branched, erect perennial herb forming compact bushes up to 300 x 300 mm; entire plant pubescent, hairs admixted erect eglandular and glandular, with the stems completely glandular hairy. Leaves opposite to subopposite except for the inflorescence where alternate; lateral veins c.3 each side of midrib, evident but not prominent; petiole 2-6 mm long, finely winged; lamina 13-33 x 7-154 mm, dull green, narrowly obovate, apex acute, base attenuate, margins serrulate, bearing 8-24 teeth. Inflorescence and flowers nodding. Pedicels 2-8 mm long. Ovaries 12-35 mm long, glandular puberulent, admixed with erect eglandular and appressed glandular hairs. Floral tube 1.8-2.8 x 2.2-3.2 mm, internally bearing a conspicuous ring of long hairs. Sepals 1.8-2.8 x 2.2-3.2 mm, not keeled, hairs admixed glandular/eglandular. Petals 7.3-13.0 x 7.0-8.0 mm, white flushed pink or pink; apical notch 1.8-3.5 mm deep. Anthers 2.7-2.9 x 0.8-1.0 mm, yellow, filaments white, those of long stamens 2.0-3.6 mm, short 1.0-2.2 mm long. Style 4.0-5.0 mm, white, often with long hairs near base; stigma 2.0-3.0 x 1.3-2.0 mm, white, broadly clavate. Capsule 2.9-4.2 mm, finely glandular/eglandular pubescent, with pedicel slightly elongated (up to 9 mm long). Seeds 0.9-1.1 x 0.4-0.5 mm, dark brown, obovoid, papillose, the coma 3.5-5.0 mm, deatched readily or persistent.
Similar taxa
Allied to Epilobium pubens A.Rich. from which it differs by its much larger, compact, bushy, rather than slender scarcely branched growth habit; by its longer sepals ( 5.0-6.5 cf 2.5-2.8 mm) and petals (7.3-13.0 cf. 3.5-7.0 mm); and by its restriction to subalpine or alpine usually greywacke rock habitats of the main axial ranges of the North Island, rather than being a widespread species of no particular substrate preference, and ranging from coastal habitats to the upper montane forest and subalpine scrub.
Flowering
December - February
Flower colours
Red/Pink, White
Fruiting
January - April
Propagation technique
Easily grown in a pot or in a rock garden in full sun. Dislikes high humidity. Quite drought tolerant.
Threats
Not threatened. Listed because it is a narrow range endemic of limited geographic extent. It is regarded as common in the few places from which it has been recorded.
Substrate
Greywacke and limestone
Etymology
epilobium: From the Greek epi- ‘upon’ and lobos ‘a pod’, the flowers appearing to be growing on the seed pod.
astonii: After Aston
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange 16 July 2005. Description adapted from Raven & Raven (1976) with seed description adapted from Webb & Simpson (2001).
References and further reading
Raven, P.H.; Raven, T.E. 1976: The genus Epilobium in Australasia. New Zealand DSIR Bulletin 216. Wellington, Government Printer.
Webb, C.J.; Simpson, M.J.A. 2011: Seeds of New Zealand Gymnosperms and Dicotyledons. Christchurch, Manuka Press.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Epilobium astonii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-astonii/ (Date website was queried)