Scientific Name:
Trichomanes colensoi Hook.f. in Hooker, Icon. Pl. 10, t. 979 (1854)
  • Vandenboschia colensoi (Hook.f.) Copel., Philipp. J. Sci. 67: 52 (1938)
  • Polyphlebium colensoi (Hook.f.) Ebihara & K.Iwats. in Ebihara et al., Blumea 51: 240 (2006)
Holotype: New Zealand, between Waikare Lake [Lake Waikaremoana] and Ruatahuna, W. Colenso 104, 1844, Herbarium Hookerianum, K! (photo WELT E469/26)
Named in honour of William Colenso (1811–1899), British-born printer, missionary and botanist, resident in New Zealand from 1834.

Terrestrial or rupestral ferns. Rhizomes long-creeping, filiform, c. 0.2 mm diameter, bearing dense red-brown hairs up to 0.5 mm long. Fronds 35–150 mm long. Stipes 3–40 mm long, not winged, brown proximally becoming green distally, glabrous or with a few scattered clavate hairs. Laminae 1-pinnate-pinnatifid near apex to 2-pinnate-pinnatifid at base, or 2-pinnate-pinnatifid throughout in large plants, elliptic or narrowly elliptic or obovate in largest fronds, 25–125 mm long, 10–30 mm wide, dark green, membranous, bearing scattered clavate hairs along veins. Rachises not winged, green, bearing scattered clavate hairs. Primary pinnae in 6–15 pairs, widely spaced, ovate or narrowly ovate, winged at their distal end, stalked at their proximal end, occasionally a few with long caudate apices greatly exceeding other pinnae; the longest primary pinnae near the middle, 10–25 mm long, 4–15 mm wide. Secondary pinnae ovate or elliptic or narrowly elliptic or obovate, winged; the distal secondary pinnae on each primary pinna adnate, the proximal stalked; the longest secondary pinnae 4–9 mm long, 2–4 mm wide. Ultimate segments narrowly elliptic, often deeply divided, up to 5 mm long, 0.4–1.2 mm wide, with veins forking 1–2 or rarely 3 times in each; apices acute, never emarginate; margins entire, lacking a border. Sori borne on short acroscopic segments near bases of primary or secondary pinnae, 1 or rarely 2 on each primary pinna, adnate or stalked; indusia tubular, 1.5–2 mm long, widened at mouth; sporangia borne on a fine receptacle up to 12 mm long, projecting well beyond the indusia at maturity.


Trichomanes colensoi is similar in appearance and habitat to T. endlicherianum. It is distinguished by its very finely divided fronds, lack of a wing on the rachis, stalked pinnae, lamina segments lacking a border, and adnate or stalked indusia. It is distinguished from T. venosum by its non-epiphytic habitat, dark green frond, much finer ultimate segments, and lamina segments which are never emarginate.


North Island: Auckland, Volcanic Plateau, Gisborne, Taranaki, Southern North Island.

South Island: Western Nelson, Sounds Nelson, Westland, Otago, Southland, Fiordland.

Chatham Islands.

Altitudinal range: 15–960 m.

In the North Island Trichomanes colensoi is found in montane forest from the Kaimai Ranges, extending east through the Urewera district to inland Gisborne and south to western Waikato and Mt Taranaki. It is found more abundantly in lowland to montane areas from the Tararua Ranges south to Wellington city. It is apparently absent from Northland, and most of Auckland, the central North Island and east coast. It grows from near sea level to 960 m on Maungatapere near Matawai. In the South Island it is largely confined to lowland areas of the west coast, extending from the Marlborough Sounds and north-west Nelson, through Westland and Fiordland, to Riverton and Dunedin. It occurs from about 15 m to nearly 560 m in the Kokatahi River catchment, Westland. There is a single collection from the Chatham Islands (AK 229973), but it is absent from Stewart Island.


Occurs on damp rock, under overhangs or beside streams in dark, wet, podocarp, beech or broadleaved forest. It frequently grows with T. endlicherianum and bryophyte species.

Indigenous (Endemic)

Trichomanes colensoi (as Polyphlebium) was given a conservation status of Naturally Uncommon by de Lange et al. (2013).


n = 36 (Brownlie 1958).


In the classification of Ebihara et al. (2006), Trichomanes colensoi is treated as Polyphlebium colensoi.

Brownlie, G. 1958: Chromosome numbers in New Zealand ferns. Transactions of the Royal Society of New Zealand 85: 213–216.
Brownsey, P.J.; Perrie, L.R. 2016: Hymenophyllaceae. In: Breitwieser, I; Heenan, P.B.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 16. Manaaki Whenua Press, Lincoln.
Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand ferns and allied plants. Edition 2. David Bateman, Auckland.
Copeland, E.B. 1938: Genera Hymenophyllacearum. Philippine Journal of Science 67: 1–110.
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. [Not Threatened]
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. [as Polyphlebium colensoi (Hook.f.) Ebihara & K.Iwats.] [Naturally Uncommon]
Ebihara, A.; Dubuisson, J.-Y.; Iwatsuki, K.; Hennequin, S.; Ito, M. 2006: A taxonomic revision of Hymenophyllaceae. Blumea 51: 221–280.
Hooker, W.J. 1854: Icones Plantarum. Vol. 10. Pamplin, London.
Iwatsuki, K. 1982: Studies in the systematics of filmy ferns VI. The genus Sphaerocionium in Asia and Oceania. Journal of the Faculty of Science, University of Tokyo, Section III. Botany 13: 203–215. [as Polyphlebium colensoi (Hook.f.) Ebihara & K.Iwats.]