Asplenium trichomanes subsp. quadrivalens
Common names
spleenwort
Biostatus
Native
Category
Vascular
Structural class
Ferns
Detailed description
Plants tetraploid. Rhizome stout, erect, bearing dark brown subulate scales up to 5 mm long. Stipes 10–100 mm long, dark brown, shining, stiff, lacking scales except at the very base. Laminae linear, 50–300 mm long, dark green, sub-coriaceous, pinnate. Raches dark brown, shining, stiff, lacking scales. Pinnae sub-sessile, 15–25 (or more) pairs, oblong to more or less orbicular, crenate-serrate to more or less entire, 2–10 × 1–5 mm. Sori up to 3 mm long. Spores 34–39 microns long.
Similar taxa
Easily recognised by the stiff and erect, simply pinnate fronds which are < 30 mm wide; bearing > 8 pairs pinnae; and by the brown stipe and rachis which is completely without scales. Two cryptic subspecies exist, one is hexaploid (2n = 216) and so has larger spores and is further distinguished by having larger darker scales while subsp. quadrivalens is tetraploid (2n = 144), so has smaller spores. It has finer, smaller, lighter scales.
Distribution
Indigenous. New Zealand: North Island (known only from a few collections from the eastern Hawke’s Bay where it was discovered in 2008 at a few sites). Also Australia, Europe and probably elsewhere.
Habitat
Unclear. Apparently lowland and at one site (Tangoio) it was collected from limestone outcrops. Other than that we know very little about it. It is suspected that a few collections probably came from gardens, and their status as representing truly wild populations is suspect.
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 | Threatened – Nationally Critical | Qualifiers: Sp, DPR, DPT, RR, SO
Threats
Unknown. This subspecies has only been collected a few times in New Zealand and recent attempts to rediscover it at these locations have so far been unsuccessful.
Detailed taxonomy
Family
Aspleniaceae
Synonyms
None
Taxonomic notes
The other widespread plant referred to A. trichomanes is a hexaploid which appears to be endemic to New Zealand (it maybe in Australia). This cytorace may yet be described as a new subspecies or even subspecies as part of a European based revision of the A. trichomanes complex (L. Perrie pers. comm.). Until that time we retain the name A. trichomanes for this widespread hexaploid fern.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Propagation technique
Difficult—should not be removed from the wild.
Other information
Etymology
asplenium: From the Greek a- ‘without’ and splene ‘spleen’, a northern hemisphere species, the black spleenwort (Asplenium adiantum-nigrum), was once believed to be a cure for diseases of the spleen.
trichomanes: From the ancient Greek name used by Theophrastus and Dioscorides, for a type of fern; refers to the slender hair projecting from each spore case
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.
ASPTSQ
Chromosome number
2n = 144
Previous conservation statuses
2017 | Threatened – Nationally Critical | Qualifiers: DP, RR, SO, Sp
2012 | Threatened – Nationally Critical | Qualifiers: RR, SO, Sp
2009 | Data Deficient | Qualifiers: SO
2004 | Data Deficient
Referencing and citations
References and further reading
Brownsey PJ. 1977. A taxonomic revision of the New Zealand species of Asplenium. New Zealand Journal of Botany 15(1): 39–86. https://doi.org/10.1080/0028825X.1977.10429618.
Attribution
Description from Brownsey (1977).