Epilobium krulleanum
Common names
willowherb
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 | Data Deficient
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Detailed description
Tufted, perennial herb 60-195 mm tall, much-branched from woody base, perennating from basal buds; stems densely leafy, initially decumbent, soon becoming erect; plants ± densely covered throughout with short, crisp, erect or appressed hairs, mostly confined to lines decurrent from the margins of the petioles, especially on upper part of stem. Leaves opposite, those within inflorescence alternate, coriaceous, longer than or equal to the stem internodes; lateral veins not prominent, 2-3 on each side of the midrib; petiole 0-3 mm; lamina 3-20 × 1-4 mm, glaucescent to dark purple-green, ovate or ovate-oblong, base attenuate, apex subacute to rounded, entire or obscurely, serrulate, and then with 3-8 weak teeth on each side. Inflorescence erect, the flowers confined to the upper portion stem. Flowers erect. Ovaries 6.5-15.2 mm long, finely and uniformly stigulose, pedicellate, pedicels 1.3-7.1 mm long. Floral tube 0.6-1.3 × 1.9-2.5 mm, adaxially strigulose. Sepals 3.8-4.5 × 2.7-4.2 mm, ovate-lanceolate, not keeled, strigulose. Petals 5.6-9.0 × 3.8-5.5 mm, pink, darkening to rose-pink after pollination, notch 1.2-1.6 mm deep. Stamen filaments white, of two types: long (1.8-4.0 mm long) and short (1.3-2.5 mm long). Anthers 0.6-1.4 × 0.5-0.8 mm, cream. Style 2.8-6.0 mm long, white; stigma 1.0-2.5 x 0.6-0.7 mm, white, clavate, surrounded by the longer or both sets of stamens at anthesis. Capsule 18-28 mm long, glaucescent, glabrous, stiffly erect, on a pedicel 6-18 mm long. Seeds 1.3-1.8 mm long, brown, obovate, apex rounded, base subacute, papillate; coma 6-8 mm long, white, caducous.
Similar taxa
Allied to Epilobium hectorii which is where Raven & Raven (1976) included it. However, it is distinguished from Epilobium hectorii by its pink flowers (which flush rose-pink after pollination), distinctly larger (5.6-9.0 × 3.8-5.5 mm cf. 2.5-8.2 × 1.8-4.3 mm) petals. which are more deeply notched (1.2-1.6 mm cf. 0.9-1.4 mm in E. hectorii) and by its larger seeds (1.3-1.8 m cf. 0.8-1.3 mm in E. hectorii) which are brown rather than orange or orange-brown, and distinctly papillate rather than finely reticulate. In Epilobium krulleanum the coma is also longer (6-8 mm cf. 4-6 mm long in E. hectorii). Both species are occasionally sympatric in part of their range, though as a rule Epilobium krulleanum has a more restricted range, and it is more common in Marlborough than elsewhere.
Distribution
Endemic. New Zealand: South Island (eastern from the headwaters of the Awatere and Clarence Rivers south through Hanmer, Canterbury and Central Otago).
Habitat
Montane to alpine on stony ground, in tussock grassland, in frost flats and on rock outcrops in open country.
Threats
Although Epilobium krulleanum is regarded as Not Threatened, partly because of its merger with the very common and widespread E. hectorii by Raven & Raven (1976) the species has been overlooked by most field botanists over the last 35 or so years. Therefore accurate information about the status of E. krulleanum is lacking, and the species may yet be better referred to as “Data Deficient” to encourage botanists to survey for the species. Many of the habitats it was recorded from in the past are now heavily modified and in some of these places, e.g., Broken Hill and the Tresslick Basin, brief searches for the species in 2000 did not rediscover it.
Detailed taxonomy
Genus
Family
Taxonomic notes
Raven & Raven (1976) adopted a very conservative treatment for New Zealand Epilobium, nevertheless in their treatment of E. hectorii, they discuss E. krulleanum and make comments which suggest that it is a distinctive species, their merger being influenced by plants attributed to this species by others, and which came from the southern part of the range of E. krulleanum. Subsequent work by field botanists such as the late A.P. (Tony) Druce and others suggest that E. krulleanum is amply distinct from E. hectorii, and although Webb & Simpson (2001) follow Raven & Raven (1976) they note that the seeds of E. krulleanum readily distinguish it from the rest of the range of E. hectorii. While it is clear that New Zealand Epilobium are in need of a modern revision, and one that is based firmly on molecular data to help establish a sensible phylogenetic framework for such a revision, in the interim, it seems sensible to reinstate E. krulleanum as species distinct from E. hectorii.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
December - January
Fruiting
December - April
Life cycle and dispersal
Minute pappate seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed. Dislikes humid conditions.
Other information
Etymology
epilobium: From the Greek epi- ‘upon’ and lobos ‘a pod’, the flowers appearing to be growing on the seed pod.
Chromosome number
2n = 36
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 | Data Deficient
2012 | Data Deficient
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Otago: 2025 | Regionally Data Deficient
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
Referencing and citations
References and further reading
Cheeseman, T.F. 1925: Manual of the New Zealand Flora. Wellington, Government Printer
Raven, P.H.; Raven, T.E. 1976: The genus Epilobium in Australasia. New Zealand DSIR Bulletin 216. Wellington, Government Printer.
Thorsen, M.J.; Dickinson, K.J.M.; Seddon, P.J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309.
Webb, C.J.; Simpson, M.J.A. 2011: Seeds of New Zealand Gymnosperms and Dicotyledons. Christchurch, Manuka Press.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (4 September 2011). Description adapted from Cheeseman (1925), Raven & Raven (1976), Webb & Simpson (2001) and herbarium specimens.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Epilobium krulleanum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/epilobium-krulleanum/ (Date website was queried)