Hypolepis millefolium
Common names
thousand leaved fern
Biostatus
Native
Category
Vascular
Structural class
Ferns
Flower colours
No flowers
Detailed description
Rhizome subterranean, long-creeping, 1.5–3.0 mm diameter, glabrous or bearing scattered pale brown hairs (especially near growing point), stipes arising at intervals of 15–130 mm. Stipes 50–350 mm long, 1.5–3.0 mm diameter, red-brown below, pale brown above, a few pale or reddish brown hairs along stipe. Laminae rhombic, ovate or broadly ovate, 150–400–(700) × 80–250 mm, membranous to slightly coriaceous, normally tripinnate (bipinnate in smallest specimens) at apex to quadripinnate or sometimes almost 5-pinnate at base. Rachis pale brown to yellowish green, bearing pale brown or colourless eglandular hairs c. 1 mm long. Primary pinnae in 20–25 pairs, the lowest arising at 30–50° to stem, upper ones at 70–90°, opposite below, subopposite or alternate above, the longest below middle 70–260 × 35–130 mm; lowest pinnae 35–150 mm apart, middle pinnae 15–50 mm apart; upper pinna narrowly ovate, lower ones ovate, midrib narrowly winged towards apices. Secondary pinnae narrowly ovate to ovate, midribs broadly winged, 25–80 × 10–35 mm, those on the lower pinnae decreasing in length along the pinnae. Tertiary pinnae 5–20 × 3–10 mm, 2-6 deep serrations per pinnule. Quaternary pinnae 0.1–0.5 × 0.1–0.4 mm, sometimes deeply divided. Hairs: glistening, colourless, scattered along midribs of pinnae and pinnules, on both surfaces, up to 1 mm long. Veins reaching margin at tooth apex. Sori: one on each ultimate segment, though often absent from lowest two pairs of pinnae, originating away from margin, unprotected at maturity or partially covered by a green reflexed marginal flap. Spores pale brown, echinate.
Similar taxa
Hypolepis millefolium is easily recognised on account of its brittle, vivid bright green to yellow-green and finely divided (‘lacy’) fronds. From other New Zealand Hypolepis it is also distinguished by the unprotected (or scarcely so) sorus; brittle stipes and fertile fronds which are 1.5–5.0 mm diameter; absence (or near absence) of glandular hairs; by the laminae of the fertile fronds > 400 × 250 mm, with the ultimate segments < 1 mm wide; and by the complete absence of hairs from the sorus.
Distribution
Endemic. New Zealand: North Island (Mt Pirongia and East Cape south, though mostly from the Central Volcanic Plateau, Mt Egmont and main axial ranges. One unusual, North Island lowland record from a roadside near Kihikihi may have came from plants that temporarily established there from road machinery that had been used to work the Western Taupo Road where this fern is common), South Island, Stewart Island/Rakiura, Chatham Islands, Antipodes Islands, Auckland Islands and Campbell Island/Motu Ihupuku.
Habitat
Coastal to alpine, In northern part of range virtually confined to montane–alpine areas but descending to sea level on the Subantarctic islands. Hypolepis millefolium is a common fern of grassland and rock strewn slopes. It also extends into scrub and forest. On the Chatham Islands it grew in restiad peat bogs, while on the subantarctic islands it grows amongst tussock grassland and open Dracophyllum scrub.
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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- 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 | Not Threatened
Detailed taxonomy
Family
Dennstaedtiaceae
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Life cycle and dispersal
Minute spores are wind dispersed (Thorsen et al., 2009).
Propagation technique
Hypolepis millefolium is very attractive fern that is easily grown from fresh spores and rooted pieces. Despite its typical associated within montane to alpine habitats it can be grown easily at low elevations. Unlike many other Hypolepis, H. millefolium is less inclined to be short-lived and, as a rule is less ‘weedy’.
Other information
Etymology
hypolepis: From the greek hypo (under) and lepis (scale), referring to the position of the sori on the ferns
millefolium: Many leaved; from the Latin mille and folium
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
HYPMIL
Chromosome number
2n = 104
Previous conservation statuses
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
Brownsey PJ, Chinnock RJ. 1984. A Taxonomic revision of the New Zealand species of Hypolepis. New Zealand Journal of Botany 22: 43–80. https://doi.org/10.1080/0028825X.1984.10425234.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309. https://doi.org/10.1016/j.ppees.2009.06.001.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (7 November 2012). Description from Brownsey & Chinnock (1984).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Hypolepis millefolium Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/hypolepis-millefolium/ (Date website was queried)