Tmesipteris sigmatifolia
Common names
fossil fern, fork fern
Biostatus
Native
Category
Vascular
Structural class
Ferns
Detailed description
Plants usually epiphytic sometimes terrestrial. Rhizomes far-creeping, buried within host bark or tissue, or buried within leaf litter, branched, lacking roots. Aerial stems pendulous, 60–280 mm long, undivided. Lamina spirally arranged, 10–20 mm long, bright green to dark green, distinctly sigmoid or narrow-oblong, coriaceous, apices blunt, midrib distinct, prolonged beyond lamina as a fine mucro. Sporangia (synangia) yellow-green, confined to the base of the upper side of the lamina, somewhat inconspicuous, unequal, testiculate with rounded apices, usually confined to upper portion of stem.
Similar taxa
Distinguished from the other New Zealand species by the sigmoid (sigma-shaped), mucronate, leaf-like lamina and small, rather inconspicuous, unequally sized, testiculate pairs of sporangia.
Distribution
Indigenous. North Island (from Te Paki south to about Thames in the east and near Wanganui in the west), South Island (from Nelson, North-west Nelson and Westland). Present also in New Caledonia.
Habitat
Coastal and lowland forest. Usually epiphytic on tree fern trunks but also found growing terrestrially in deep leaf litter. In the northern part of its range it grows mostly within kauri (Agathis australis (D.Don.) Lindl.) forest.
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 | Not Threatened | Qualifiers: SO
Threats
A naturally uncommon and biologically sparse species. It is never common at any particular site and is often known from only a few specimens over wide parts of its range. It would be fair to say that it is undercollected and so in part our knowledge of this species is inadequate. Nevertheless it does not seem to be threatened, partly because it requires mature forest, much of which is already protected over large parts of its known range.
Detailed taxonomy
Family
Synonyms
Tmesipteris tannensis var. elongata Sahni
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Propagation technique
Difficult—should not be removed from the wild
Other information
Where To Buy
Not commercially available
Etymology
tmesipteris: From the Greek tmesis (cutting) and pteris (fern), alluding to the forked appendages on fertile fronds
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.
TMESIG
Chromosome number
2n = 208
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 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Sparse
Referencing and citations
References and further reading
Chinnock RJ. 1975. The New Zealand Species of Tmesipteris (Psilotaceae). New Zealand Journal of Botany 13(4): 743–768. https://doi.org/10.1080/0028825X.1975.10430356.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (June 2009). Description adpated from Chinnock (1975).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Tmesipteris sigmatifolia Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/tmesipteris-sigmatifolia/ (Date website was queried)