Nomenclature
Scientific Name:
Tmesipteris sigmatifolia Chinnock, New Zealand J. Bot. 13: 764 (1975)
Synonymy:
Holotype: New Zealand, Northland, Waipoua Kauri Forest, Toronui Track, 0.2 km from Waipoua River, R.J. Chinnock P302, 26 Oct. 1972, CHR 271740!
  • = Tmesipteris tannensis var. elongata Sahni, Philos. Trans., Ser. B 213: 143, pl. 5, fig. 5-6 (1925) nom. illeg.
Etymology:
From the Latin sigma (S-shaped) and folium (leaf), a reference to the leaf shape.
 Description

Epiphytic ferns. Aerial stems pendent, 40–270 mm long, 10–35 mm wide, unbranched or rarely 1-branched, of indeterminate growth terminated by large sterile leaf or sporophyll. Leaves narrowly oblong or narrowly ovate, usually sigma-shaped, spirally arranged, shiny green on both surfaces, coriaceous; the longest 8–20 mm long, 2–4 mm wide, just above or just below mid-stem; apices slightly emarginate, truncate or cuspidate, with a mucro 1.5–3.5 mm long. Sporophylls mostly in the distal half of the stem or sometimes throughout except for the lowermost part. Synangia 2.5–5 mm long, 1–2.5 mm high; lobes often unequal in size or occasionally equal, round-ended; the lower surface of each lobe appressed to the subtending leaf margin along its length.

 Recognition

This species is recognised by its generally sigma-shaped leaves which are narrower than in other species and with a longer mucro tip. The synangia are usually located in the distal half of the stem, and the lobes are often unequal in size, with rounded ends.

 Distribution

North Island: Northland, Auckland, Gisborne.

South Island: Western Nelson.

Altitudinal range: 0–400 m.

Tmesipteris sigmatifolia occurs throughout Northland and Auckland, as far south as Thames, with outlying populations on Mt Pirongia and near Kāwhia Harbour, and isolated records in the far eastern Bay of Plenty between Waihau Bay and Pōtaka. In the South Island, there are very sporadic and imprecisely located 19th century collections of the species from the Maitai Valley, Nelson and in Westland (Chinnock 1975, in overseas herbaria), but only one 20th century collection from the Pororari River, Westland (CHR 500815). In the North Island it grows to 300 m or more in the Puketi, Herekino and Maungataniwha Forests, and up to 400 m on Mt Pirongia and on Great Barrier Island.

Also New Caledonia.

 Habitat

Tmesipteris sigmatifolia grows epiphytically on tree fern trunks, most commonly on Cyathea dealbata and Dicksonia squarrosa, but also occasionally on Cyathea medullaris, Dicksonia lanata, and, at higher altitudes, on Cyathea smithii. It has been recorded once growing in litter at the base of a kauri (CHR 302370). It occurs in kauri, podocarp, broadleaved and old kānuka forests in northern New Zealand.

 Biostatus
Indigenous (Non-endemic)
 Cytology
 Bibliography
Brownsey, P.J.; Given, D.R.; Lovis, J.D. 1985: A revised classification of New Zealand pteridophytes with a synonymic checklist of species. New Zealand Journal of Botany 23(3): 431–489.
Brownsey, P.J.; Lovis, J.D. 1987: Chromosome numbers for the New Zealand species of Psilotum and Tmesipteris, and the phylogenetic relationships of the Psilotales. New Zealand Journal of Botany 25(3): 439–454.
Brownsey, P.J.; Perrie, L.R. 2015: Psilotaceae. In: Breitwieser, I; Heenan, P.B.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 9. Manaaki Whenua Press, Lincoln.
Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand ferns and allied plants. Edition 2. David Bateman, Auckland.
Chinnock, R.J. 1975: The New Zealand species of Tmesipteris (Psilotaceae). New Zealand Journal of Botany 13(4): 743–768.
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. [Not threatened]
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. [Not Threatened]
Sahni, B. 1925: On Tmesipteris viellardii Dangeard, an erect terrestrial species from New Caledonia. Philosophical Transactions of the Royal Society of London, Series B, containing papers of a Biological Character 213: 143–170.