Diplazium australe
Biostatus
Native
Category
Vascular
Structural class
Ferns
Detailed description
Terrestrial tufted ferns (often deciduous in cooler areas). Rhizome to 80 mm long, erect over time forming a short, woody caudex, initially covered with dull dark brown to black scales. Fronds arcuate, glabrous membranous, brittle, dark green, groove of rachis open at junctions with grooves of pinna midribs. Stipe 150–800 mm long, black and scaly at the base, deeply 3-grooved. Lamina 3-pinnate, 0.25–1.2 × 0.2–0.9 m, broadly deltoid. Pinnules 5–25 × 2–10 mm, oblong; base broadly attached to axis; margins bluntly toothed or shallowly lobed less than half-way to costule, abaxially decurrent; apex obtuse. Sori 2–3 mm long, 3–5 per pinnule, elongated along one side of a vein, mostly single, sometimes paired along both sides; indusium pale brown, elongated, attached to vein on one side, free edge toothed, fragile.
Similar taxa
Diplazium australe is sometimes confused with Deparia petersenii subsp. congrua, with which it often grows, partly because both Diplazium and Deparia have sori arranged in a herring bone pattern, a pattern which may also lead to confusion with Asplenium. However both Diplazium and Deparia differ from Asplenium by the sori which are paired back-to-back along the veins. Diplazium differs from Deparia by its much larger, more divided, glabrous fronds and by the groove of the rachis which is open and confluent with the grooves of the pinna midribs (rather than not open at junctions with grooves of pinna midribs).
Distribution
Indigenous. New Zealand: North Island, South Island (though mostly absent from the drier eastern side of both islands, reaching its apparent southern limits in the west near Greymouth and in the east in the Marlborough Sounds). Also Australia (eastern Queensland, eastern New South Wales, southern Victoria and Tasmania) and Norfolk Island.
Habitat
Coastal, lowland to montane forested habitats, common in alluvial forest, along river flats, in gullies,or swamp forest. Often found in rough pasture or under willows. Often found in urban areas.
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 | Not Threatened | Qualifiers: SO
Detailed taxonomy
Family
Athyriaceae
Synonyms
Allantodia australis R.Br., Athyrium australe (R.Br.) C.Presl; Athyrium umbrosum subp. australe (R.Br.) C.Chr.; Athyrium umbrosum var. australe (R.Br.) Domin; Athyrium brownii (J.Sm.) J.Sm.; Athyrium umbrosum sensu Cheeseman; Asplenium australe (R.Br.) Brack.; Asplenium brownii J.Sm.; Asplenium umbrosum sensu G.M.Thomson; Allantodia tenera R.Br.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Life cycle and dispersal
Minute spores are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easy from spores and rooted pieces. Very fast growing and inclined to become weedy. Prefers a shaded site but copes well in full sun provided it is planted in permanently damp ground. In cooler parts of the country it dies down to the rhizome during winter.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACU: Facultative Upland
Occasionally is a hydrophyte but usually occurs in uplands (non-wetlands).
Other information
Cultivation
Occasionally available from mainline and specialist native plant nurseries
Status notes
This species was once considered to be very uncommon. It appears to have flourished and expanded its New Zealand range as a result of human disturbance and is now one of our most widespread, weedy, indigenous, urban ferns.
Etymology
diplazium: From Greek diplasios ‘double’, referring to the double covering over the spores
australe: Southern, from the Latin australis
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.
DIPAUS
Chromosome number
2n = 246
Previous conservation statuses
2017 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
Brownsey PJ, Smith-Dodsworth JC. 2000. New Zealand Ferns and Allied Plants. David Bateman, Auckland, NZ. 168 p.
Jones DL. 1998. Athyriaceae. Flora of Australia 48, Ferns Gymnosperms and allied groups: 418–429. ABRS/CSIRO Victoria, Australia.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309. https://doi.org/10.1016/j.ppees.2009.06.001.
Rothfels CJ, Sundue MA, Kuo Li-Y, Larsson A, Kato M, Schuettpelz E, Pryer KM. 2012. A revised family-leve classification for eupolypod II ferns (Polypodiidae: Polypodiales). Taxon 61(3): 515–533. https://doi.org/10.1002/tax.613003.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (18 January 2012). Description adapted from Brownsey & Smith-Dodsworth (2000). Family follows Rothfels et al. (2012).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Diplazium australe Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/diplazium-australe/ (Date website was queried)