Species

Diplazium australe

Etymology

Diplazium: from Greek diplasios 'double', referring to the double covering over the spores
australe: southern, from the Latin australis

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened

Authority

Diplazium australe (R.Br.) N.A.Wakef.

Family

Athyriaceae

Flora Category

Vascular - Native

NVS Species Code

DIPAUS

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.

Structural Class

Ferns

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.

Distribution

Indigenous. New Zealand: North and South Islands (though it is 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.

Features

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 pairs 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).

Flowering

Not applicable - spore producing

Flower Colours

No Flowers

Fruiting

Not applicable - spore producing

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.

Threats

Not Threatened

Chromosome No.

2n = 246

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Minute spores are wind dispersed (Thorsen et al., 2009).

Where To Buy

Occasionally available from mainline and specialist native plant nurseries

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.






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).

References and further reading

Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand Ferns and Allied Plants. Auckland, David Bateman

Jones, D.L. 1998: Athyriaceae. Pp. 418-429. Flora of Australia 48. Australian Biological Resources Study, CSIRO Canberra

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 11: 285-309

Rothfels, C.J.; Sundue, M.A.; Kuo, Li-Y.; Larsson, A.; Kato M.; Schuettpelz, E.; Pryer, K.M. 2012: A revised family-leve classification for eupolypod II ferns (Polypodiidae: Polypodiales). Taxon 61(3): 515-533

This page last updated on 4 Dec 2014