Asplenium haurakiense
Common name
Hauraki Gulf spleenwort
Synonyms
Asplenium flaccidium subsp. haurakiense Brownsey
Family
Aspleniaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Ferns
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.
ASPHAU
Chromosome number
2n = 288
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) – more information about this can be found on the NZTCS website. This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. 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. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened
Previous conservation statuses
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Distribution
Endemic. New Zealand, Three Kings Islands, Northern North Island to Waitakere Coastline in the west and Whale (Moutohoura) Island in the east
Habitat
Strictly coastal. Mostly terrestrial, growing in exposed or sheltered sites, often in positions subject to salt spray, also in petrel scrub and on small offshore islands it frequently grows around petrel burrows in dense forest.
Features
Mostly terrestrial. Rhizome short, stout, erect, bearing dark brown ovate scales with very thick cell walls, up to 20 × 2 mm. Stipes 50-200 mm (or more) long, brown on underside, green above, firm and erect, sparingly covered in small ovate scales with very thick walls. Laminae oblong to elliptic, 100-400 (or more) × 40-200 mm, ± dull or more often glossy green, thick, leathery, stiff and erect, pinnate to bipinnate. Raches green, sparingly scaly. Pinnae in 5-20 (or more) pairs, linear to narrowly ovate, acuminate, long stalked, 20-150 × 5-20 mm; degree of dissection very variable, sometimes only divided into very short obtuse segments, sometimes pinnate. Pinnules oblong and obtuse to linear and acute, up to 8 × 2 mm. Basal acroscopic pinnule frequently much longer than that next to it, up to 40 mm long, and itself pinnatifid. Sori submarginal, linear, 2-7 mm long. Spores (38-)43-49(-54) micrometre long, (20-)26-31(-38) micrometre wide
Similar taxa
Allied to Asplenium flaccidum G.Forst. from which it differs by its mostly terrestrial growth habit, restriction to coastal areas, octoploid (2n = 288) rather than tetraploid (2n = 144) chromosome number, ovate rhizome and stipe scales (with very thick cell walls); stiffly erect rather than pendulous, usually glossy green rather than dull green, oblong to elliptic fronds; by the basal acroscopic pinnule which is frequently much longer than that next to it, up to 40 mm long, and itself pinnatifid; and by the larger spores. Asplenium appendiculatum subsp. maritimum (Brownsey) Brownsey occupies similar coastal habitats and is somewhat similar. It can be distinguished from A. haurakiense by its allopatric distribution, and by the lack of a greatly elongated basal acroscopic pinnule on each pinna.
Flowering
Not applicable - spore producing
Flower colours
No flowers
Fruiting
Not Applicable - Spore Producing (Healthy plants produce spores throughout the year)
Life cycle
Minute spores are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easily grown. A very attractive fern which can be rather slow growing. Best in a large pot or planted in a deep, rich, moist soil in semi-shade. Prone to scale and mealy bug infections. A very variable species which could benefit from critical horticultural selection.
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.
Where To Buy
Occasionally sold by plant and specialist native plant nurseries.
Notes on taxonomy
Brownsey (op cit.) treated this fern as a subspecies. However, it is frequently sympatric with A. flaccidium s.s., and on occasion hybridises with it, producing sterile hybrids. Accordingly NZPCN prefer species rank. Kermadec Island group plants referred to A. flaccidium are perhaps closer to A. haurakiense. Further study is needed.
Attribution
Description modified from Brownsey (1977)
References and further reading
Brownsey, P.J. 1977: A taxonomic revision of the New Zealand species of Asplenium. New Zealand Journal of Botany 15: 39-86.
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 2009 Vol. 11 No. 4 pp. 285-309