drooping filmy fern, Irirangi, piripiri
Mecodium demissum (G. Forst.) Copel.; Hymenophyllum australe var. aucklandicum (Bosch) C.Chr.; Sphaerocionium demissum (G.Forst.) C.Presl; Trichomanes demissum G.Forst.; Hymenophyllum aucklandicum Bosch;
Vascular – Native
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.
2n = 72
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). 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.
2012 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
Endemic. New Zealand: Kermadec (Raoul Island), North, South, Stewart, Chatham and Auckland Islands. Widespread except for the drier parts of the eastern South Island
Coastal to montane in forest. Usually terrestrial where it typically forms dense carpets on the ground, on banks or on rotting logs. Also epiphytic, and then found mostly on the basal trunks of forest trees and tree ferns. Sometimes found in forest growing over boulders, rocks and on cliff faces.
Terrestrial or epiphytic fern forming large patches made up of numerous densely (more rarely diffuse) packed fronds. Rhizomes long-creeping, slender. Stipes 40-170 mm long, stout, pliant, wiry, glabrous usually not-winged, if winged then wing minute; rachises narrowly winged throughout. Laminae elliptic, ovate or narrowly ovate, 3-4-pinnate, 70-250 × 30-150 mm, pale green to dark green, glabrous. Ultimate segments oblong, margins smooth. Sori numerous on the terminal ends of the ultimate segments of the primary pinna. Indusial flap margins smooth or minutely toothed. Description adapted from Brownsey & Smith-Dodsworth (2000).
Easily recognised by the extremely wiry usually un-winged stipe, large glabrous fronds, smooth-margined pinna segments, and when fertile by the numerous, narrow, paired sori. When dry the fronds of this species rarely curl up.
Minute spores are wind dispersed (Thorsen et al., 2009).
Difficult - should not be removed from the wild
hymenophyllum: Membranous leaf, from the Greek humen and phullon
demissum: Drooping; from the latin demissus; referring to the leaves when the plant is perched on trees
Where To Buy
Not commerically availabe
Fact Sheet Prepared for NZPCN by P.J. de Lange (17 April 2011). Description adapted from Brownsey & Smith-Dodsworth (2000).
References and further reading
Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand Ferns and Allied Plants. Auckland, David Bateman
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
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Hymenophyllum demissum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/hymenophyllum-demissum/ (Date website was queried)